Whenever I try to set Junk Control Settings (JCS) to move junk to the respective Junk folders for each account on manual tagging or whenever I try to extend the period of auto-demention of junk older than 14 days it won't accept changes when I press 'OK' to quit the dialog. Actually, It won't accept ANY changes at all no matter what it is I try to change. The Settings simply stay as they were (which currently is NOT the default but a state I was obviously setting some time earlier). Also you might be interested into knowing that I installed the GDATA AntiVirenKit (antivirus software that uses a loopback 127.0.0.1 to filter out virus-mails, there is a 'Use VirusGuard With Thunderbird 0.6' setting within its preferences). Once, I wasn't paying attention while scanning so it put my whole junk folders (from all accounts) into quarantine. I used the Restore Button within this anti-virus software to restore them to the default profile... I can only guess but it appears that it was sine then when these unchangable JCS appeared. FYI, I have 2 accounts atm, one from my ISP one from a freeservice provider, I think both are via POP, since the mail server addy seems that way.

(Q1) Did you change prefs.js manualy to "127.0.1.1" for GDATA AntiVirenKit? Or change was made by GDATA AntiVirenKit. Check your next entries of prefs.js. - mail.server.serverNN.hostname - mail.server.serverNN.realhostname (if exists) - mail.server.serverNN.userName - mail.server.serverNN.realuserName (if exists) If mail.server.serverNN.hostname and mail.server.serverNN.userName were changed(by any of you or AntiVirenKit), next will be a recovery procedure. (1) Change mail.server.serverNN.hostname and mail.server.serverNN.userName to initial setting(real server name and real user name). (2) Change server name and user name from "Thunderbird's UI" to 127.0.0.1 and required username for anti-virus software. Thiese changes will be saved in - mail.server.serverNN.realhostname - mail.server.serverNN.realuserName Change on server name / user name after initial account definition should be written in mail.server.serverNN.realhostname and mail.server.serverNN.realuserName. It is your fault, if you changed mail.server.serverNN.hostname and mail.server.serverNN.userName. It is anti-virus software's fault, if an-ti-virus software changed mail.server.serverNN.hostname and mail.server.serverNN.userName.

Thanks for the reply! It was changed by the AntiVirenKit, I did not notice until I was recieving unusually often a request for password entry upon mail transers even though I had already been typing in the master password (which is set to use for entire thunderbird session only). Upon examination I noticed it had been set to loopback in the smtp mail servers. I then changed it back and disabled the AntiVirenKit VirusGuard feature for Thunderbird 0.6 mail clients. So it's a bit of both, mine and the fault of the anti-virus kit. will post again when I looked up and tried your suggestions for fixing this issue. thanks again for letting me know.

See Bug 213300 for other damages by mail scaning function of anti-virus softwares. Then close as DUP of Bug 221386, please, because many of bugs are DUPed to this. If further problem occurs in recovery, post a comment. Good luck.

Will do. Thanks again. This bug has been marked as DUP of bug #221386. *** This bug has been marked as a duplicate of 221386 ***

Yes, it worked as you mentioned. I manually fixed prefs.js and now it is working again. I made sure simply that all identities have the same hosts and user names entered. It even was possible to just change the prefs file than actually entering it within the TB UI. Only downside is that it is now downloading my plenty of mails again since the first message noted. Should take a while :) Anyway, Thanks wada!