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Thunderbird hangs my machine periodically

Thunderbird causes my machine to 'hang' from time to time, often for up to a second and usually a number of times in quick succession on each ocasion. Sometimes this happens frequently - say every 5 or 10 minutes - sometimes only after an hour or more since the past occurrance. My machine hangs completely - nothing will work, mouse, keyboard, sound, other apps etc. If I happen to be typing (into any app - including Thunderbird - when this happens, input ceases, the cursor freezes and - if the problem persists for a second or two, Windows reports "[app] is not responding" I cannot be certain, but I believe the problem occurs whilst messages are being retrieved.

This is a very serious problem as it means that I can never leave TB running as the problems it causes are not acceptable. This means I cannot deal with incoming messages without periodically re-starting TB - which is an utter PIA.

I am running Win 11 Professional on a 2-year old machine with 64 Gb of memory. I have run TB in Troubleshoot mode, I have confirmed that the problem occurs regardless or whatever other apps are running (or none) and I have proven conclusively that no other app causes any kind of similar problem.

Looking forward yto hearing if others have had the same issue and what can be done about it.

Thunderbird causes my machine to 'hang' from time to time, often for up to a second and usually a number of times in quick succession on each ocasion. Sometimes this happens frequently - say every 5 or 10 minutes - sometimes only after an hour or more since the past occurrance. My machine hangs completely - nothing will work, mouse, keyboard, sound, other apps etc. If I happen to be typing (into any app - including Thunderbird - when this happens, input ceases, the cursor freezes and - if the problem persists for a second or two, Windows reports "[app] is not responding" I cannot be certain, but I believe the problem occurs whilst messages are being retrieved. This is a very serious problem as it means that I can never leave TB running as the problems it causes are not acceptable. This means I cannot deal with incoming messages without periodically re-starting TB - which is an utter PIA. I am running Win 11 Professional on a 2-year old machine with '''''64 Gb of memory'''''. I have run TB in Troubleshoot mode, I have confirmed that the problem occurs regardless or whatever other apps are running (or none) and I have proven conclusively that no other app causes any kind of similar problem. Looking forward yto hearing if others have had the same issue and what can be done about it.

All Replies (7)

Have you tried windows safe mode with networking? I suggest you do.

Can I ask why are suggesting that might help please? Are you suggesting that to run Thunderbird I will always need to run in Safe mode?

I have already done the obvious and checked that Email and calender services are enabled in the Win Defender firewall.

... I should also add that this is not a new problem - it has existed since i first installed TB when this machine was new and had almost nothing else installed. I have raised the matter only now simply becuase it has finally driven crazy ...

Wayne Mery; thank you for that link. However, it seems to refer to Thunderbird performance issues. I specifically stated that my problem is that Thunderbird hangs my WHOLE MACHINE. That is a highly specific problem and I cannot see any reference to that in the 4850 words within that link. In fact, when my machine is not hung by it, Thunderbird performs very well indeed.

Could someone please address my specific question???

Applications which induce OS hangs (almost) always have a fundamental underlying problem in the OS.

So the advice Matt provided earlier is spot on - first test is you running Windows in safe mode with networking enabled. (That advice is also in the checklist)

Modified by Wayne Mery

Wayne Mery, many thanks for your further response.

I confess to feeling just the slightest bit frustrated by this. Bearing in mind that this is an intermittent issue, it is 'almost impossible' to test in Safe Mode because the environment is so limiting - for example, I cannot (say) run a music streaming app, or a graphic-dependent app to see if they 'hang' when I send external emails to TB, nor can I get on with any useful work whilst TB runs in the background.

I fully agree that TB has a " fundamental underlying problem in the OS ". However, Safe Mode is not the Operating System I normally use, and not a single one of the other (several dozen) Apps I run has any such problem in normal mode.

I would like to move to the next step please, so let me say "I have been unable to reproduce the fault through the very limited testing I have been able to do in Safe Mode". ... which does not mean that the problem does not exist in Safe Mode - merely that I have no means of surfacing it without wasting half a day typing into TB or some such.

I would add that for 99% of the time, I cannot reproduce it in normal mode either. But it is the 1% which is the nuisance.

Sual ver

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