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Thunderbird Not Responding Windows 10

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  • Last reply by sfhowes

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I'm using Thunderbird 78.10.1 (64bit) on Windows 10 Pro. The app keeps jamming with a message in the menu bar: Not Responding Also, when I open Thunderbird, Windows Program Compatibility Assistant (PCA) gives me continuous alerts that "an app can't run on this device". Have you had this problem before? I was going to try to switch to 32bit Thunderbird to see whether or not the problem goes away. Can I just delete this version of tbird and install the other version without losing my profile and email messages?

I'm using Thunderbird 78.10.1 (64bit) on Windows 10 Pro. The app keeps jamming with a message in the menu bar: Not Responding Also, when I open Thunderbird, Windows Program Compatibility Assistant (PCA) gives me continuous alerts that "an app can't run on this device". Have you had this problem before? I was going to try to switch to 32bit Thunderbird to see whether or not the problem goes away. Can I just delete this version of tbird and install the other version without losing my profile and email messages?

Chosen solution

try reinstalling the 64 bit version if that is what you have. I don't get mad messages about compatibility on windows 10 64bit.

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Chosen Solution

try reinstalling the 64 bit version if that is what you have. I don't get mad messages about compatibility on windows 10 64bit.

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Thanks for your reply. I did try reinstalling the application. I still have frequent jamming with the message: Not Responding. It usually takes a wait of about 10 to 20 seconds for the page to reset, the message disappears and I the application unjams.

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I've never seen an example of 'not responding' depending on whether TB is 32 or 64 bit. Both work on 64-bit Windows. 'Not responding' is typically caused by some external app, such as antivirus, and it's recommended to run Windows in safe mode to bypass startup apps and then test TB. If the error remains in Windows safe mode, there are a number of factors that can cause it.

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Your suggestion is good. In Safe Mode there's no problem. So what I think I'll do is to reinstall Windows 10 keeping my files and folders. That will essentially uninstall all of my 3rd party software. Then I'll reinstall the apps as I need them one at a time over several days and see which one is causing the problem. Any other ideas would be appreciated. Thanks again for helping.

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You could first look at the Startup tab in Task Manager (right-click the Start button) for possible sources, such as AV or online backup software. The solution might be as simple as excluding the TB profile folder from AV scanning (leaving the real-time background scan in place), which is the general recommendation for all AV apps and TB. For other apps, disable them one-at-a time on the Startup tab and test TB performance. These steps are easier than reinstalling Windows, although that has its own advantages.

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Thanks for your input. As you say, there are advantages to reinstalling Windows and so that's what I'll try. Pleasure speaking with you.

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Something new. So, I decided to stop Defender's scan of TB as you suggested before renewing Windows 10. Well it was mostly successful. It stopped the constant "Not Responding" and the PCA popups occur only every few minutes. That solves the main problem I was having. I'd still like to know what program periodically causes the PCA popup or how to completely stop the PCA notification. Any Suggestions??

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I've no idea why the PCA is appearing with TB 78 on W10, but a quick search shows there is a simple way to disable it:

http://www.door2windows.com/how-to-disable-program-compatibility-assistant-pca-in-windows-7-vista/

Check Task Manager for any process that may be related to network connections that is causing the popups.