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"Unable to connect to your IMAP server. You may have exceeded the maximum number of connections to this server. If so, use the Advanced IMAP Server Settings dia

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  • Last reply by Jeff M

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I am receiving the ""Unable to connect to your IMAP server. You may have exceeded the maximum number of connections to this server. If so, use the Advanced IMAP Server Settings dialog to reduce the number of cached connections." error message.

I am running Thunderbird version 68.2.1 under windows 10. There are four accounts connected via Thunderbird. I also connect using a Samsung S9.

I have tried varying the number of permitted IMAP connections between 1 and 10 with no result. I have also disabled the Norton incoming email scan, again to no avail. As a last resort, I have tried switching off the phone to make sure it's IMAP connection is closed but this also makes no difference. The strange thing is that all of the accounts seem to be working perfectly.

Doesn't seen to make any sense.

I am receiving the ""Unable to connect to your IMAP server. You may have exceeded the maximum number of connections to this server. If so, use the Advanced IMAP Server Settings dialog to reduce the number of cached connections." error message. I am running Thunderbird version 68.2.1 under windows 10. There are four accounts connected via Thunderbird. I also connect using a Samsung S9. I have tried varying the number of permitted IMAP connections between 1 and 10 with no result. I have also disabled the Norton incoming email scan, again to no avail. As a last resort, I have tried switching off the phone to make sure it's IMAP connection is closed but this also makes no difference. The strange thing is that all of the accounts seem to be working perfectly. Doesn't seen to make any sense.

All Replies (17)

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The error you are seeing indicates that the server has set a limit in the total amount of connections that you can make with your account (across all devices at that current time) and you have reached that limit.

It results in the exceeded max number of connections message that you are seeing.

Reducing the amount of folders that you are synchonising should resolve this issue. It can also help if you increase the checking for new mail interval to at least 10 minutes.

Set a lower threshold in Thunderbird for each mail account. Account Settings > Server Settings > 'Advanced' button Choose lower than 5 eg: 3 or even 1

Phones, ipad etc: eg: Make sure the Samsung has disconnected from server and is temporarilly switched off.

To force closure of connections to reset everything:

For one of your accounts:

  • Right click on imap mail account in Folder Pane and select 'Settings'
  • Select 'Server Settings'
  • uncheck 'check for new messages at start up'
  • uncheck 'check for new messages every xx minutes'
  • uncheck 'allow immediate server notifications when new messages arrive'
  • click on 'Advanced' button
  • set the 'max number of server connections' to 3
  • click on OK
  • Click on OK

Restart Thunderbird. See what happens when you start Thunderbird. If no improvement restore all 3 of check for new messages etc, set 'check for new messages every 10 minutes' or more, but leave the mac connections set as 3. Then do the same process for another account. Repeat until checked all accounts.

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same issue and reduced to 2. - no change. ISP SKY who have changed e-mail client password necessity. However, whilst one A/C fixed with SKY 16 letter password second A/C (second user on same PC) getting this message. If change to SKY 16 letter password for e-mail client will it not off the first user's A/C? Or do I need to bother?

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re :second user on same PC

As more than one user is using the PC, after booting up computer, does each user then logon to their own computer 'User Account' to see their own desktop and their own folders and files in general?

It is usual for each user to have their own computer 'User Account' as this is offers the user an important level of security. Each User Account can be setup to have their own password to gain access.

Thunderbird is installed on the computer and can be used via 'User Accounts'. When you initially run Thunderbird in each User Account, a default profile is created and stored within each User Account. This means any mail accounts are also stored separately. As a password is required to gain access to the User Account, it means emails etc are not visible to anyone who does not know the 'User Account' password.

If the second user is accessing the same email address, then any password change on server will effect all mail accounts that access the same email address. One email address has one password regardless of whether you access that email address via webmail account or via any imap or pop mail account on any computer.

If you are getting the too many connections error that is a message from the server saying you have opened the maximum connections allowed by server. Changing the cache connections to a lower number will force connections to close at a lower number to help stop you attempting to open too many. Those 'connections' include all connections to that email address regardless of whether they are made from phones and various computers. So, I suggest you make sure all people accessing that same email address, have set a lower cache connection and disconnect all connections to that email on all computers and phones to get it reset. Please allow a little time before reconnecting as server may need time to fully disconnect all cached connections.

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I think I get it. Detail: x1 PC W10 64 pro. x2 users on PC each with separate SKY a/c. Repeated IMAP unable to connect. SKY recommended on a/c #2 delete a/c and reinstall. Did this - but still got the message. Found out SKY now require e-mail client authentication as per https://www.sky.com/help/articles/secure-your-sky-yahoo-mail-account put in that password generated 16 letter to a/c #2 - got into Thunderbird, then asked for Yahoo mail password. seems to have worked. On a/c #1 the IMAP message persists. Reduced cache value to 2 and deleted various defunct folders on SKY. The question now, if doesn't settle do I delete a/c #1, generate the one-off SKY 16 letter password and reactivate? Given the one-off 16 letter password has been used - is the same password necessary for a/c #1 or will a new one suffice? SKY haven't a clue what to do and the change password for e-mail client link above I found outside of SKY. I can use Thunderbird on a/c#1 just annoying message that maybe deleting defunct folders in SKY / Yahoo will help. Otherwise it is the SKY e-mail client authentication 16 letter password route after deleting a/c#1. Does this make any sense? cheers

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re :x2 users on PC each with separate SKY a/c. sky says: If your email app setup doesn’t meet certain security standards, you’ll soon no longer be able to sign in using your usual password and you’ll need to generate a unique 16-digit app password instead.

If each sky account is a different email address then each will/should have a separate password. Therefore each will need their own app specific password as it relates to the email address.

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Thanks each a/c has a separate e-mail password for yahoo and each yahoo e-mail has different user I.D. e.g. X @sky.com and Y @sky.com. Hence do I delete a/c #1, generate a one-off SKY 16 letter authentication from SKY for this a/c, then re-install a/c using the SKY 16 letter password and onwards? Or, do I change the password to the SKY 16 letter password in Thunderbird without deleting the a/c? Thanks for your guidance. cheers

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I would try the latter first as it is quick to do and you always have the option of deleting and recreating account if it is being a pain. change the password to the SKY 16 letter password in Thunderbird without deleting the a/c.

Options > Options > Security > Passwords click on 'Saved Passwords' click on 'Show passwords' You will see two lines for each mail account. Incoming will start with either imap:// or mailbox:// and outgoing will start with smtp:// Both need updating. right click on line to get option to Edit Password. Clear content and retype carefully the correct app password. click on 'Close' Then restart Thunderbird to force it to use the saved data.

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Thank you for all of your replies...

To clarify,

1) There is only one user account on this PC. There are four email accounts accessed via Thunderbird.

2) The problem is intemittent and all of the email accounts seem to be updating normally.

I have currently edited the IMAP server connection on all of the accounts from 10 to 3 (wasn't able to be sure which if the accounts was causing the issue). I am now waiting to see if this has brought about a permanent cure... intermittent faults are a PITA.

I will respond appropriately when I am confident that I know what the results are.

Thanks again

RF

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To Toad-Hall thanks that seems to have worked. It did require x2 Thunderbird re-starts to restabilise. But the connectivity, with x4 restarts thereafter seems stable once again many thanks regards J P.S. what is annoying that SKY tech team on phone did not know, and someone else found the solution of the one-off 16 letter authentication password necessity on SKY. Doubly annoying in that today so many purchases etc require e-mail.

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Darn returned again Delete a/c and restart? Presumably require new SKY generated password

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update: despite uninstalling Thunderbird and the roaming profiles (which had returned on a reinstall) and giving each a/c a new profile and a generated SKY password and waiting whilst Thunderbird updated and reducing and also increasing server connections to cache. The problem remains. I also x-posted to SKY forum. Hence neither Mozilla nor SKY support fora can provide a solution despite doing everything recommended, confirming ports, uninstalling and reinstalling Thunderbird several times including deleting roaming profiles. I feel sorry for individuals who may be elderly and faced with similar issues who have to get someone to look at the issue, pay them - only for no solution. I suppose that I am slightly disappointed that neither Mozilla nor SKY communities can provide a solution.

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despite numerous attempts - still states unable to connect to IMAP server. one SKY forum response is that SKY now prefer users to use browser not e-mail client - anyone got comments? The 16 letter password does not work.

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re :one SKY forum response is that SKY now prefer users to use browser not e-mail client - anyone got comments?

You will find that just about all eg: Yahoo, Gmail, etc prefer you to use their webmail because they can bombard you with adverts. Their help can also is very much limited to webmail help, they often have very little knowledge of Imap/pop/smtp.

By the way, it is not Mozilla who is offering support, it is other Thunderbird users freely volunteering their time. It would be helpful if someone using Sky could help out.

SKY are forced to change because Yahoo have changed.

I was looking on the general yahoo website, just in case it offers better instructions

  1. Sign in and go to your Account security page.
  2. Click 'Generate app password' or 'Manage app passwords'.
  3. Select 'your app' from the drop down menu and click 'Generate'.
  4. Follow the instructions below the password.
  5. Click Done.
  6. Use this app password and your email address to sign in to your email app.

The infor above says if you are signing in to a specific account for a specific email address and then creating the 16 digit password, then that 16 digit password then replaces normal password when signing in using Thunderbird for that specific email address, so is seems specific per account and not per app.


How does this yahoo info compare to what you see when you logon to SKY? Did you get the option shown as number 3 to be able to select what app eg: Thunderbird ? I was wondering if you generated the password but did not specifiy the app.

Check this: In the SKY webmail account is there an option to switch on something like 'Allow less secure apps' ? If yes, then select it.

Whilst Yahoo offer OAUth2 for imap, I do not think this is rolled out generically for all using the yahoo server. I believe Yahoo & AOL have OAuth2 since TB version 60.0. When SKY talk about email client offering enhanced security, the problem is that SKY are not necessarilly offering it as yet. Thunderbird cannot use the oAuth2.0 authentication until SKY are prepared to issue tokens for mail applications to use. Not exactly totally helpful at the moment.

Check your server settings are up to date just inc ase SKY have altered anything. Incoming server information: Host Name/Server: If you're using POP3: pop.tools.sky.com If you're using IMAP: imap.tools.sky.com

Port: If you're using POP3: 995 If you're using IMAP: 993

Connection Security: SSL/TLS Authentication Method: Password

Username: Your full Sky Yahoo Mail address e.g. username@sky.com Password: Your Sky iD password

Outgoing server Information: Outgoing mail server: smtp.tools.sky.com Outgoing server port: 465 Connection Security: SSL/TLS Authentication Method: Password

Username: Your full Sky Yahoo Mail address e.g. username@sky.com Password: Your Sky iD password

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Many thanks Toad Hall. 1. settings confirmed OK by SKY originally and re-checked. 2. SKY/ Yahoo settings are really very limited in ability to customise / amend. 3. SKY forum members response was to ditch Bitdefender and use W10 defender. However, I have contacted Bitdefender and await reply. If I recall correctly whilst Windows defender has improved it still ain't top notch e.g. ransomware defence, when I was switching from Avira to any other. A firtle on Mozilla suggested Bitdefender was an issue with TB - but many moons ago - McAfee is the biggest culprit.

Anyhow I have taken the bull by the horns and have stopped trying to solve TB and gone for free eM Client. So far touch wood is OK along with Bitdefender after 36 hours. OK I liked TB, but hours on computer trying to solve the issue is now wasted time.

I'll see how things go. But many thanks for all your detailed input and support - it is much appreciated. kind regardx J

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final update: message from SKY Dear Jxxxxxx,

We’ve noticed that you may be accessing your Sky.com email on your mobile, tablet or other device using an out-of-date version of an email application such as Apple Mail, Outlook or Windows Live Mail.

To ensure a better and more consistent experience for all our customers, out-of-date versions of these email applications will no longer be supported by Sky.com email from 10/12/2019.

This means you will need to update your email application to the latest version, which will include new features, enhanced security standards and better usability.

If you decide not to update your email application, you will no longer be able to access your Sky.com email using this method from 10/12/2019.

However, you will still be able to access your Sky.com email via Sky.com

To verify this email and get all the help you need, please head to sky.com and click on the section titled ‘Help accessing Sky mails via email apps’ on the homepage.

Please note you do not need to reset or change your password for your Sky.com email address.

Kind regards,

Sky


So it seems that SKY are definitively blocking "out of date" e-mail clients. I did try TB 64 bit (for 64 bit computer and hard to find) - worked then crashed yet again. I erased TB 32 bit by uninstall + clear app data roaming and local = CCleaner registry before installing TB 64 bit. And used SKY password and then 16 letter password. So TB 32 and 64 didn't work including full uninstall and clear. SKY forum commentators suggest a "local" thing, but as computer is fully operational and a SSD test was full pass - I am struggling to understand. Some suggested Bitdefender, but I am sure many have TB + Bitdefender with no issue.

So I have given up, regrettably, with TB. I cannot make it work with SKY / Yahoo tanks all for help offered.

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This forum has same issue as you, but people find the 16 digit password works. https://helpforum.sky.com/t5/Email/Anyone-having-issues-accessing-their-sky-emails/td-p/3094685

Sky should block if using normal pasword, but not if using 16 digit because they explicity request it.

We don't currently support email apps that we haven't already covered above. If you use another email app, the following information might help you to set up your emails.

Username: Your full Sky Yahoo Mail address e.g. username@sky.com Password: Your Sky iD password

I also notice SKY say this: You can no longer create a new email account via Sky as we no longer offer this service.

Makes you wonder how long SKY are going to keep working. Perhaps it's time to consider a new email account with someone more reliable.

Advise you do not allow CCleaner any access to Thunderbird or other email clients as they mess up required files.

Sorry, things are not working out.

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Thanks for all your clear help over this period - it is much appreciated. My thread on SKY is https://helpforum.sky.com/t5/Email/Unable-to-connetc-to-IMAP-server-etc-on-Thunderbird/td-p/3099397.

Interestingly the same responders are on both threads, yet no cross referencing of threads to illustrate issues.

I would change from SKY however, a) gmail a/c I have is a tad cumbersome by comparison with 2 stage entry and then says "you've been using gmail on another device (phone or computer)" is that right - every time and b) most of my e-mail addresses are to e.g. government agencies such as DVLA and so have to wait until they expire - about 12 months.

I have been with SKY for aeons - before yahoo mail was contracted and with TB - and it is annoying how things become corporately deteriorated.

I'm a 'point and shoot' user not an under-the-bonnet type except when i have to. I seek help in desperation. And while the internet is a magical thing in many ways, I was born and did my doctoral thesis on a BBC B and daisy wheel printer with 7" diskettes - x1 diskette per chapter circa 1987. Now one almost needs a masters degree to fix software and the constant updating. At times I rue progress and the inability to fix simply. As I age life is becoming ever more unreliable and complicated.

Hey ho us coffin dodgers become more Meldrewish with time methinx.

But as you say, unless there is a backlash, SKY e-mail may well be doomed.

As an aside on the Mozilla / TB front - if one Googles the message thrown up by TB "unable to connect to IMAP...........", there are references going back > a decade with the same problem on the mozilla bug list bugzilla. So it ain't all knew. best wishes

J