Your not messing with windows 10 in safe mode.... you are preventing startup applications like ESET from actually loading. I would guess probably a 50% or better change of it being the issue. Possibly as high as 90% except for you also having ccleaner. My system has certainly been faster without ESET.

Then I read you have the worst simple cause of Thunderbird disasters ccleaner installed. I hope you have everything to do with Thunderbird turned off, out of the box it is a disaster, simply deleting setting files is not helpful at all and that is the default configuration.

You need to actually stop ESET via safe mode as it could be the on access scanning for files, The scanning of "encrypted" connections, or any of several other "features" that causes issues. Having an exemption for the Thunderbird profile folder in there is a must as you can not have an antivirus scanning 4 or 5 Gb file every time they are opened (the global database often is more than a gigabyte in size.) as are Gmail all mail folders.

You might also want to rebuilt the global database. If the issue is antivirus and on access scanning it may be what it contains is never really getting updates so updates are reading months of journals to determine what to index because the database is out of date. https://support.mozilla.org/en-US/kb/rebuilding-global-database

Have you tried disabling the windows search and indexing service from access to the Thunderbird profile. This certainly made things faster for me when I had a standard slug speed platter disk in my Dell desktop. That system also had 8Gb of ram with 4 of those devoted to the graphics card. Thunderbird truly struggled with my profile with 4Gb of RAM.

Is your system generally having a fast drive and lots of free disk space? Despite there being some truly silly system specification on the web site, Thunderbird does not do will without probably 10% or more of the local disk as free space. (it will grab up to 5% of the local disk space for a cache.) The web site says you only need 200MB to install Thunderbird. That is not even enough to actually install a 64bit version. Thinking in terms of a 20Gb free and you will be getting closer.

Thank you so much for your reply.

All you have to is "touch" windows and... cross your fingers and toes. I don't like adjusting Windows unless someone on the phone tells me what to do, and even then I'm reluctant and have to be sure I can put things back how they were before I made changes. Have had bad experiences fiddling with windows.

In lieu of booting Windows in safe mode, I can "pause" ESET to temporarily disable it, but that had no effect on my Tbird indexing hang. For a long time now eset has been set to exclude Tbird.

My laptop is Win10 with eset/cCleaner and Tbird IMAP and it's fine. My other desktop is Win10 with eset/cCleaner and Tbird POP and it's fine.

"Have you tried disabling the windows search and indexing service from access to the Thunderbird profile." I don't know what that means. I know you're trying to help me but due to past experiences on my own and with techs, I don't like making changes to windows OS. I haven't had to disable that on the other two computers.

16 GB ram and an SSD with 237 GB free space. Figured that was sufficient.

In cCleaner, yes there are a couple of Tbird checkboxes ON. I'll turn them off but like I say, it's ok on the other two computers. I'll look in to rebuilding the Global Database. What do you think about uninstalling/reinstalling Tbird 102 and copypasting the Mozilla/Thunderbird Folders from the IMAP Laptop?

You may not like it, but my experience with these antivirus tools is they actually lie. They do not go off when you tell them to and continue to wreak their havoc when "paused"

Have you actually looked at what is involved in a safe mode restart on windows 10? I suggest you do. I am linking to Microsoft's pages on this as they are the experts. I note that in one example you hold shift while you click the power button on the screen. https://support.microsoft.com/en-us/windows/start-your-pc-in-safe-mode-in-windows-92c27cff-db89-8644-1ce4-b3e5e56fe234

Now one of the reasons you may ind you only have to touch windows is your choice of security. The easiest way to mess up windows is to change security setting to supposedly increase security settings. In my experience this goes back as far as Internet explorer 4. But we are not talking about changing anything here, just using a built in startup mode provided by Microsoft for the purpose of diagnosing problems.

Disabling the search and indexer in the profile is as simple as locating the folder in file explorer, right clicking the folder and selecting the advanced button and removing the checkbox entry. That is not messing with windows. That is customizing for your use. I would recommend doing that with the profile folder, and the mail and imapmail folders it contains.

Have you rebuilt the global database? You need to.

I would like to thank you for your time, expertise, and patience in helping me resolve this matter.

Yes the antivirus tools lie and aren't quite all the way OFF when "paused." Understood.

Yes, I have booted Windows in safe mode a few times for diagnostics but that was many years ago in previous versions. As long as Windows boots back up normally I'm ok with using safe mode but that's about all I really want to change in windows. Win10 safe mode doesn't alter windows, it just turns off some things, i.e., virus program, so you can do diagnostics. Understood.

I have not yet disabled the windows search and indexer in the profile or the mail and imap mail folders. Even though it's easy to do, I'm reluctant but will cross that bridge when I come to it.

I have not yet rebuilt the Tbird global database. It dawned on me that I first should have tried webmail using firefox to make sure there's no mail issue at the internet provider. Webmail works fine. Then, right there on webmail I started cleaning out some imap mail folders I created, i.e., one had 750 messages, hence the slow reply back to you cause it's taken a few days.

After deleting 300 of 750 messages in that one folder, Tbird started working normally. I cleaned that specific folder first cause that's the folder Tbird hung on indexing. Deleting those messages may have reduced the size of the global database, if that was part of the problem as opposed to it being corrupt. I'll continue with the house cleaning and if Tbird continues working correctly then I probably won't rebuild the gloda. If need be I'll come back and hopefully you'll be available.

I appreciate you.

> After deleting 300 of 750 messages in that one folder, Tbird started working normally. I cleaned that specific folder first cause that's the folder Tbird hung on indexing. Deleting those messages may have reduced the size of the global database, if that was part of the problem as opposed to it being corrupt.

Probably then just a bad message causing fits for global indexing.

Deleting such a small number of messages would not have significantly reduced the size of the global database

I have not been able to get Thunderbird to work properly. I've reached the point of needing to uninstall and reinstall. I can very easily use AddRemove Programs, but instead of just going ahead and doing that, I would like to ask if there is anything in particular I should do or not do given that it's IMAP Win10? In other words, given Tbird 102, IMAP, Win10 what's the best way for me uninstall and reinstall?