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Error code: PR_CONNECT_RESET_ERROR

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I cannot use Firefox or Thunderbird I keep getting an error code: PR_CONNECT_RESET_ERROR The problem started straight after the latest update a few days ago.

I have cleared the cache and cookies I turned off the addons and extensions I shut down the internet security I changed the proxy settings to "no proxy" I even changed cert9 to ccert9 and had firefox generate a new cert9

Nothing has worked.

HELP!

I cannot use Firefox or Thunderbird I keep getting an error code: PR_CONNECT_RESET_ERROR The problem started straight after the latest update a few days ago. I have cleared the cache and cookies I turned off the addons and extensions I shut down the internet security I changed the proxy settings to "no proxy" I even changed cert9 to ccert9 and had firefox generate a new cert9 Nothing has worked. HELP!

Chosen solution

It was the Russian!!! I decided to un-install Kaspersky and wipe out every last vestige of it. Now everything works.

It would seem that if you just turn Kaspersky off, or leave anything behind it will make its presents known.

I have re-installed Kaspersky, and all seems to be well so far. But if the Russian causes any more trouble he will be out on his ear.

I have never been impressed with the logic of Kaspersky's human interface and I have always found their websites are terrible to navigate and you go round and round circles looking for something and never finding it. Also it is all but impossible to get support. But I have persisted with them for over 10 years because its the first Internet Security Program I have had that has not let anything through.

If he does misbehave again I don't know what AV I will go with - Any suggestions?

Anyway, thanks for the help.

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All Replies (7)

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I'm guessing Windows? What security software are you running? What version of Firefox?

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G'day jonzn4SURE

Thanks for your reply.

I am running the following:-

Device name DESKTOP-V1GE34A Processor Intel(R) Core(TM) i5-4440 CPU @ 3.10GHz 3.10 GHz Installed RAM 8.00 GB (7.86 GB usable) Device ID 00F21627-9D16-4698-BC0D-CF7931852CB2 Product ID 00330-80000-00000-AA866 System type 64-bit operating system, x64-based processor Pen and touch No pen or touch input is available for this display

Edition Windows 10 Pro Version 22H2 Installed on ‎19/‎11/‎2020 OS build 19045.4894 Experience Windows Feature Experience Pack 1000.19060.1000.0

Firefox 130.0.1 (64-bit)

Thunderbird 115.15.0 (32-bit)

Kaspersky Internet Security Kaspersky VPN was installed but not activated (I un-installed it yesterday to see if it would help)

I could live without Firefox as Google Chrome and MS Edge are working, but I would prefer not to be beholden to Bill or Google.

As for Thunderbird, I need it, because changing email program will be a big issue, and I do not want to go to MS Outlook as I do not want to sign up for a monthly subscription to MS365 (sound like MS13 times 28 + 1).

I was wondering if I download a Thunderbird64-bit version and install it, will it transfer all my emails and accounts automatically, and over-write the 32-bit version. Or am I asking for trouble doing that?

Just a side note, I installed Duck Duck browser when the problem started. It worked for an hour and then came up with the same error. But Google Chrome and MS Edge still work, not an issue.

So I thought I need a Chromium based browser, thinking it may not succumb to the problem. I then installed UNGoogled Chromium. It worked for an hour and succumbed too.

70 to 72 hours after it all started Google Chrome and MS Edge are still working. Is it because Bill and Google have a supposedly "better product" (not my opinion) that they have not succumbed, or is there something going on here?

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Sorry if I am a little tardy getting back to you. I have no email because of this problem, so I do not get notified when there is a response to my posts.

Thanks for you patience and help.

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Thanks for the suggestions.

https://support.mozilla.org/en-US/questions/1401291#answer-1557674 Already Done this One – Did safe mode and disabled Kaspersky

https://forum.kaspersky.com/topic/getting-pr_connect_reset_error-in-firefox-when-using-kaspersky-total-security-28248/ Have Not Seen this One – But I have already disabled Kaspersky and it didn’t help. This person had a different OS and different Kaspersky product, so every thing is different. I did find the self defence button, but the Kaspersky files are different and I cannot find a file starting with AVP. While looking for the self defence button I saw a check box in Kaspersky specifically for Mozzilla products – so I told the Russian to not monitor Firefox or Thunderbird. Then rebooted, but the problem is still there. I was not hopeful as completely shutting Kaspersky down didn’t help.

https://support.mozilla.org/en-US/questions/1444114 Already Done this One - This is where I found out about cert9

Any other suggestions are welcome.

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I did fire up a very old laptop which has a very old version of Firefox on it, and it worked. There were some sites (about 40%) that I tried that Firefox could not connect to. But they were a different error and I am presuming that it is because the Firefox on the laptop is to old to connect to a lot of modern sites.

So I think that I can rule out a service provider problem.

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Chosen Solution

It was the Russian!!! I decided to un-install Kaspersky and wipe out every last vestige of it. Now everything works.

It would seem that if you just turn Kaspersky off, or leave anything behind it will make its presents known.

I have re-installed Kaspersky, and all seems to be well so far. But if the Russian causes any more trouble he will be out on his ear.

I have never been impressed with the logic of Kaspersky's human interface and I have always found their websites are terrible to navigate and you go round and round circles looking for something and never finding it. Also it is all but impossible to get support. But I have persisted with them for over 10 years because its the first Internet Security Program I have had that has not let anything through.

If he does misbehave again I don't know what AV I will go with - Any suggestions?

Anyway, thanks for the help.

Helpful?

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