Firebird is so slow now, that I can rarely receive the code that you send me. Have to take annother programm for that. Freezes even when trying to mark a mail or erasing it. WIN 11.

Hello Ed, I tried like you said: Right Click Inbox, Properties,Repair Folder,and then Compact. The same with TRASH folder. Btw: Since Download (Update) I miss the folder SPAM or so! I think it does not work better than before. When I want mark a mail it takes a long time befor it is marked f.e..

do not know what to do further!

Thank You!

Anti-virus software?

Thank You Rick! Of course, I have an antivirus SW- Mc Afee - since some Years! As I wrote before, Thunderbird was working with that good for month! But since 3 or 4 month it is remarkable slow! After an update I miss the folder SPAM and before I had the other folder instead of spam and I dont remeber its name. (Junk?) By the Way! Now, in some cases f.e. marking a mail or trying to put in another folder thunderbird freezes, and all the display is getting white for some moments. than this vanishes. when it is done. What I want to know is, what happens when I deinstall Thunderbird completely, an try to install it again, are all my data (Mail) lost or can I do it without danger? And: To receive a mail is remarkable long! Thank You in helping me!

Anti-virus software can cause many problems in Thunderbird. I believe that at least some of your symptoms can be caused by anti-virus software. The common recommendation on the forum is not to use any anti-virus software other than what Microsoft includes in Windows. If one insists on using third-party anti-virus software, one should create an exception for Thunderbird in it and read the information here: https://support.mozilla.org/en-US/kb/security-panel-settings-in-thunderbird

If McAfee is causing some problems, I do not know why they starting happening only recently. Maybe the software was updated.

You do seem to have problems other than those that are caused by anti-virus software. But removing Thunderbird and re-installing rarely fixes anything.

In your place, I would first try Thunderbird in troubleshooting mode (under the "Help" menu) and see if the problems persist or which ones persist.

If some problems persist, I would then start Windows in safe mode with netorking turned on. Some people report that this requires an Ethernet connnection because wi-fi does not work in safe mode. If you cannot do that, then disable McAfee and test Thunderbird again. I do not know if you must re-start Windows after disabling McAfee.

If you really want to remove Thunderbird, you can delete the app, which is stored separately from your profile, and you won't lose data. But back up your profile first because we all make mistakes.

You used to have a junk folder and now you have neither a junk folder nor a spam folder?

Thank You Rick! Of course, I have an antivirus SW- Mc Afee - since some Years! As I wrote before, Thunderbird was working with that good for month! But since 3 or 4 month it is remarkable slow! After an update I miss the folder SPAM and before I had the other folder instead of spam and I dont remeber its name. (Junk?) By the Way! Now, in some cases f.e. marking a mail or trying to put in another folder thunderbird freezes, and all the display is getting white for some moments. than this vanishes. when it is done. What I want to know is, what happens when I deinstall Thunderbird completely, an try to install it again, are all my data (Mail) lost or can I do it without danger? And: To receive a mail is remarkable long! Thank You in helping me!

I think Rick was suggesting you temporarily disable McAfee, or at least disable the setting to scan email messages. Please don't uninstall or reinstall TB yet.

Thank You, I will try all You said! Since Update Thunderbird there is no folder SPAM or JUNK to be seen! But TB marks Spam or Junks! Strange!