Safe mode is described at https://support.mozilla.org/en-US/kb/safe-mode

Thank you Wayne, for your response - I put TB into safe mode using the info you sent. It did not find any extensions since I had previously removed Lightning as the only extension I have used. I continued in safe mode thinking that perhaps it would stop something it didn't list. to no avail - it continued to freeze etc. as before. I then decided to try the reset option on the safe mode dialogue box and I am in day two with out a freeze or an abort. After a while I will try restarting TB normally to see what happens and I'll let you know if you'd like. Again thank you for doing what you do. I'll not check the solved box until it goes OK after a restart in a couple of days.

Unfortunately Safe Mode does not eliminate the problem although it does seem to be a little bit less of a problem. So all extensions and plugins disabled and I am still plagued by freezes and the dialogue box with the following messages:

Script: chrome://messenger/content/msgMail3PaneWindow.js:68

Script: chrome://messenger/content/folderPane.js:2128 Script: chrome://messenger/content/folderPane.js:534 Anybody have any suggestions?? It's getting to the point of changing the email client and I would hate that.

RonKearney said

Unfortunately [Thunderbird] Safe Mode does not eliminate the problem although it does seem to be a little bit less of a problem. ...

Start *Windows'* safe mode with networking enabled - win10 https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode

Still In Windows safe mode, start thunderbird in safe mode - https://support.mozilla.org/kb/safe-mode-thunderbird

Does problem go away?

> What does this mean?

BTW, to answer this part of your question - the script name typically is unimportant. The script is normally a *victim* of something else in the system that is causing Thunderbird to run slowly.

HTH

Thank you, Wayne, for the explanation of the script business. As to the win10 safe mode, I restarted the OS in safe mode and TB in it's safe mode. I could not get it to fail. I then started TB in the normal manner and it still did not fail. I then started most of what I usually have running (trading platform, TB, Chrome, task manager ( I was amazed at how little the resources are are used in safe mode)), and anything else I could think of that the system in safe mode would allow. Still no failure. I then restarted the OS in the regular manner and started TB only. In about ten minutes TB froze for about 35 seconds and came back without the dialogue box. And in about 15 minutes after that it froze for about 15 seconds after clicking on an email, again no dialogue box. And again for about 10 seconds. So even tho I didn't get a complete failure the problem seems to be active when TB and Chrome and task manager only are running. It does experience periods of quiet operation and then with no apparent provocation it will enter a period of intense activity in which it is almost impossible to end the program without aborting the process. What, if anything, can you suggest I do next?

To summarize - it only fails if both Windows and Thunderbird are NOT started in safe mode?

Which AV software are you running? (and see https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues )

"To summarize - it only fails if both Windows and Thunderbird are NOT started in safe mode?"

Not quite, In OS safe mode I could not get it to fail at all even when TB was not started in safe mode. "I restarted the OS in safe mode and TB in it's safe mode. I could not get it to fail. I then started TB in the normal manner and it still did not fail. "

As to the security software, I am running the newest Symantec/Norton AV. I followed the link you provided. The info seemed to imply that I should try putting ".../appdata/Roaming/Thunderbird" into the Norton "Real Time Exclusions" with subfolder option checked. Is that correct?

RonKearney said

As to the security software, I am running the newest Symantec/Norton AV. I followed the link you provided. The info seemed to imply that I should try putting ".../appdata/Roaming/Thunderbird" into the Norton "Real Time Exclusions" with subfolder option checked. Is that correct?

Yes.

Something loading at Windows startup is causing your problem.

Well, its been about 2 weeks since I did the business with the Norton AV and that didn't seem to help - was getting aborts and freeze ups of various lengths and plenty of dialogue boxes. But something has seemed to change, because since Sunday the 21st I have not had a failure of the TB system! My hopes are certainly up that this episode is now over. After all, the problem came suddenly so its not inconceivable that it could disappear just as suddenly. So, I thank you very much for your help over the past month and hope that this is not premature. (tempting the Gods, do to speak).

> But something has seemed to change, because since Sunday the 21st I have not had a failure of the TB system!

Great news. If it pops up again please post in this topic

Still no failures since 8/21!! Problem seems to be limited to short pauses once in a while. Thanks again for your help.