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Subfolders disappear

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Windows 7/SP3/64-bit, 16GB RAM, Avira anti-virus, also scanned by MalwareBytesAntiMalware. Was using Thunderbird 38.5.0. Upon updating to version 38.6.0 yesterday all of the non-default message subfolders in my main POP3 account disappeared. Most of the messages in them were then lumped into my main Inbox.

I was able to retrieve most of the messages by uninstalling Thunderbird, cleaning the Windows Registry with Ccleaner, installing a clean 38.5.0, and recovering the Thunderbird profile named "travel" from a day-old Acronis TIH backup.

Upon examining the contents of the old profile I wonder if it has been corrupted. See the attached image of its contents. The name of the profile is "travel." My main account is "pop.1and1.com." One subfolder, "Westminster.sbd," has been expanded to be viewed in the right-hand pane.

I note that some of the subfolders (Carriage House, Dad, Westminster) have duplicate ".mozmsgs" folders under another "main" folder named "pop.1and1.com.sbd." Also in that folder is a subfolder named "PayPal.mozmsgs" that does NOT appear in the larger "pop.1and1.com."

Is there a practical way to get a clean start of the mailboxes and move the desired subfolders from my backup copy into it? What should the "Mail\pop.1and1.com\" .mozmsgs, .sbd, .msf, and non-extension folder tree hierarchy look like? Did the handling of these subfolders change from version 38.5.0 to 38.6.0?

Thank you.

Windows 7/SP3/64-bit, 16GB RAM, Avira anti-virus, also scanned by MalwareBytesAntiMalware. Was using Thunderbird 38.5.0. Upon updating to version 38.6.0 yesterday all of the non-default message subfolders in my main POP3 account disappeared. Most of the messages in them were then lumped into my main Inbox. I was able to retrieve most of the messages by uninstalling Thunderbird, cleaning the Windows Registry with Ccleaner, installing a clean 38.5.0, and recovering the Thunderbird profile named "travel" from a day-old Acronis TIH backup. Upon examining the contents of the old profile I wonder if it has been corrupted. See the attached image of its contents. The name of the profile is "travel." My main account is "pop.1and1.com." One subfolder, "Westminster.sbd," has been expanded to be viewed in the right-hand pane. I note that some of the subfolders (Carriage House, Dad, Westminster) have duplicate ".mozmsgs" folders under another "main" folder named "pop.1and1.com.sbd." Also in that folder is a subfolder named "PayPal.mozmsgs" that does NOT appear in the larger "pop.1and1.com." Is there a practical way to get a clean start of the mailboxes and move the desired subfolders from my backup copy into it? What should the "Mail\pop.1and1.com\" .mozmsgs, .sbd, .msf, and non-extension folder tree hierarchy look like? Did the handling of these subfolders change from version 38.5.0 to 38.6.0? Thank you.
Attached screenshots

Chosen solution

Matt, I successfully updated to 38.6.0 without the previous multiple crashes. It must have been the corrupted caches you mentioned. Because I make daily backups, any messages I might have lost were still on my host's server.

I can confirm on two different Win 7/64 installations that "parent.lock" survives closing Thunderbird and re-booting Windows. I checked the running processes and services and found no hint of any remaining stubs.

If Thunderbird is re-started the file date and time just change to the current value. The presence of "parent.lock" no longer prevents the program from starting.

Thank you again for your help. Your observations and findings were accurate, your explanations were easy to understand, and your suggestions fixed the problem. These qualities are all too rare on today's Internet Help Forums.

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All Replies (4)

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your mozmsgs are for windows search. if you turn the option off you can delete the folders and their thousands of files. in my case it was a many GB of files.

The large files you see in the expanded view are what are displayed as folders in Thunderbird. This varies if you use the unified view.

Issues like you describe are more often than not cused by an update not applying to cached structures properly and deleting the file xulstore.json can clear it up. foldetree.json and panacea.dat can also be deleted to force a clear out of the caches settings.

Sessions.jsan can also be deleted, but it will revert the main interface to default. so the reading pane will be on etc.

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Thank you, Matt. I deleted the files and folders you named above with no apparent ill effects. Later I will make a backup copy of this profile and then try again to update to 38.6.0 and see if it works this time. I will report back here.

Are all of the files/folders in the attached clip still used by newer versions of Thunderbird? Some seem to have not changed for several months.

Is it normal for "parent.lock" to remain in the profile after Thunderbird has been closed?

Thanks again.

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parent.lock should be deleted on shut down.

the others, are mostly password files. I assume from that you have not had reason to change them recently.

I am not sure what the mailviews.dat file does. but it is small so it is not something I would worry about. It is probably created by an add-on as I do not have one.

I am not really aware of a full list of the files in a profile. but this one discussed the important stuff and goes very close http://kb.mozillazine.org/Files_and_folders_in_the_profile_-_Thunderbird

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Chosen Solution

Matt, I successfully updated to 38.6.0 without the previous multiple crashes. It must have been the corrupted caches you mentioned. Because I make daily backups, any messages I might have lost were still on my host's server.

I can confirm on two different Win 7/64 installations that "parent.lock" survives closing Thunderbird and re-booting Windows. I checked the running processes and services and found no hint of any remaining stubs.

If Thunderbird is re-started the file date and time just change to the current value. The presence of "parent.lock" no longer prevents the program from starting.

Thank you again for your help. Your observations and findings were accurate, your explanations were easy to understand, and your suggestions fixed the problem. These qualities are all too rare on today's Internet Help Forums.