I have been using Thunderbird on my Windows desktop as my email client for many years. Linking to GMail has always been easy and straightforward. The IMAP connection worked flawlessly. A few days ago, however, two events happened. First TB got updated to v68.7. After that I noticed Thunderbird was having difficulties connecting to the GMail, IMAP and SMTP server. There were no errors messages, just timeouts.

I have since been attempting to rectify the problem. I first thought I had a password issue but that was not the problem. I removed 2-step authorization and that did not correct the issue. Finally I removed my GMail account on Thunderbird and started fresh. No success. Now the account installation process just hangs as TB check the password. This is kind of ridiculous. None of the articles linked to by Google seem to correct the problem.

I did note a mozilla bug report Bug 1592407 that has a long thread about this issue. The fix mentioned in c22 did not work for me. So what gives. Some changes on the Google side that are incompatible with TB at this time?

nice to know I'm not the only one w/this problem.

If you look at the bugzilla site, there are a lot of people with this problem. It is a known bug in the software. Not sure why the fix has not been disseminated

There apparently was a workaround for the same or a similar problem w/v. 62. That came up during the search I did before posing my question.

I'll add to my original question that this has NOT happened with my desktop, which was upgraded to Win 10 (pro if there is a pro w/win 10) at about the same time as I got the Lenovo laptop w/win 10 installed. I just reviewed all the account settings and the desktop incoming server is set for pop.gmail.com while the laptop's incoming server setting is for imap. Guess I'll go change the server setting, et al, for the laptop and see if that fixes the problem. At least until the TB/Mozilla experts figure out what's causing the problem the imap setting, if that's really the problem's source.

I tried changing the server settings for gmail, made no difference. I'm pretty unhappy with having to go to gmail directly to use that gmail account. It's worked well enough for years with a few other problems (one of which wasn't fixed for close to 4 years), now it's not and apparently not for the first time.

Well I did some sleuthing and figured out my problem. A couple of seemingly discordant observations. I have another image of Thunderbird but using a Linux Distro (Ubuntu) for the OS. That TB version works fine. I also installed Outlook on my Windows computer - it did not work. But, good old Windows Mail worked just fine. So that kind of told me that the problem is not my Google Account per se. Clearly the Linux box with Thunderbird and the Windows box with WinMail are working OK. So this had to be some peculiar interaction with Thunderbird or Outlook and some component of my Windows laptop image.

So I started looking elsewhere and the first thing I did was disable my Internet security. Sure enough both email clients worked fine. I called the software vendor (a German company called GData) and reported the glitch. Turns out they are well aware of the problem. This happened all of the sudden and they have received loads of calls so it seems that a recent upgrade in their software along with the changes in TB caused the bug to appear. It is not only affecting TB but Outlook as well. It is related to a port scanning phenomenon. Turn off port scanning and the email clients work fine.

So it goes. I hope that this bit of sleuthing might help you as well.

I am using Windows 10 but also use Gdata's internet security, so your response is helpful/might even solve my problem. Thanks very much. I'm having another issue w/IS which I haven't reported yet so I guess I'll request tech support for both.

Thanks very much for posting the result of your sleuthing.

Hi mkostura, and thanks for your answer - I searched 2 hours before I find this solution. I found all the solutions according to version 62.0 of tb so I don't see the idea to look at gdata. The situation is the same as you describe in your first post. Since I expect that mostly german people use gdata I write down the options I have to change in german. If there is another possibility please inform us. Email-Prüfung -> weitere Einstellungen -> Erweitert -> Haken bei Eingehend (IMAP) und Ausgehend (SMTP) entfernen. Thunderbird neu starten . Thanks Karsten

Karsten The fix was not in Thunderbird. The fix is in GData. Either email check should be completely disabled or under email check, go to "More Settings" --> "Advanced" and then uncheck the boxes to scan for the IMAP server ports and the SMTP server ports.

BTW GData upgraded the software today and whatever they did was not a fix.