This bug is for phenomenon observed in duplication test for Bug 496892. If "filter move" is invoked while "compact folder" is running, both of "compact folder" and "filter move" silently fails. When "move target folder" is click after end of filter & compact, Thread Pane becomes blank, and UI hangs on the "move target folder". UI hang occurs on "move target folder" only. This was observed with both Tb latest-trunk and Tb 2.0.0.21. > Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1pre) Gecko/20090608 Shredder/3.0b3pre [Steps to reproduce] (1) Move source folder/Compact will run on this folder: 25 mails * 4MB mail, mail-1/mail-3,/mail-5 is Shift+Deleted => File Size = 100 MB, Active mail size = 88 MB. Move target folder: No mails. File size=0 Message filter: Match all message, Move to "move target folder" (2) Restart Tb, open 3 Tb windows (3) window-1 : "Compact Folder" of "move source folder" nstmp/nstmp.msf appears. (4) window-2 : While compact is running, "Run Filter On" on "move source folder" (5) "Done Cmpacting" at window-1. nstmp/nstmp.msf disappers File size of "move source folder" is still 100 MB. (6) File size increase of file for "move target folder" stops. File size is less than 88 MB => Error during "copy phase" of "filter move". (7) window-3 : Click "move target folder" => Thread pane becomes blank. UI of this window freezes. Note: Test result of above scenario is usually phenomenon like next (Bug 496892). - Compact normally ends(deleted mails is removed) - "Delete phase of mail move" fails, then result of "filter move" becomes same as "filter copy", although filter log says "All are moved". This bug's problem is timing dependent.

During test, I saw status bar display of "building summary file..." (I'm not sure "move source folder" or "move target folder"). If "move target folder", "blank thread pane" is possibly Bug 494752.

Interfere with each other? (Message filter, move XXX to YYY) (Compact Folder on XXX) Because file is opened with share option, both process can read XXX. Reading long mail data of a mail At last step of copact, tries to; <- contention ---> delete XXX.msf, XXX ---> create XXX.msf ---> rename nstmp(-N) to XXX ---> final update of data of XXX.msf Note: Bug 498814 is phenomenon for interfere of compact with file open(read, noshare) by other program which forces "file open failure" by Tb.

wada, so, when the affected folder is clicked, the UI hangs?