Can't restore backed up filter
I accidentally deleted a filter I had for a mail account. I backed up my Thunderbird data with KLS Backup. I located the backed up filter and copied it back to its original location. I, however, did not see the deleted filter in Thunderbird. I located a folder with the following path: "C:\Users\Samit\AppData\Roaming\Thunderbird\Profiles\7fqqqgxi.default\ImapMail\imap-mail.outlook.com\INBOX.sbd" that contained a file with the name of the deleted filter. Can I somehow restore the filter using this file or is the filter lost for good?
ప్రత్యుత్తరాలన్నీ (2)
I do not know what you restored, but I seriously doubt it was anything useful.
Filters are stores in a file called filterrules.dat in the root of the account, not the inbox sub folders which is what inbox.sdb signifies. They do not have individual files for each filter.
Filters are stored in a msgFilterRules.dat file in each account folder, e.g. in ...ImapMail\imap-mail.outlook.com. The .dat files can be copied between existing accounts or from backups, but check that the references to folder targets are still correct.