Update - Found a bunch of files (weird way) on the NAS in its recycle folder name "Copy #xx of <database name="">.kdbx". Took the latest one, which is 9 days old, and was able to open it. Lost a couple of new passwords I created in the last 9 days. But at least I got most of the data back by renaming this file to the original file name and opening it.
Problem - there is no option "Tools' → 'Repair KeePass Database File...'." as mentioned in the wellread1 response suggested html file. I have version 2.39.1 of the software. Also, I can find no tmp file with the same name anywhere on my system. Also my file was on a NAS with 1 million MTBF drives in it. Got a firmware update from the manufacturer. My file system disappeared. They helped me get it back. Just wasn't showing up. All files and folders were still there. I opened the keyfile once, used...
Further investigation indicates that Keepass zeroed out the file on closing.
Failed to load the specified file!
Windows 7, Active Tcl, Visual Tcl installation
I have a similar problem on Windows 7. I put the message on the open forum.
Tried getting latest version of Active Tcl's download, the free one. Got it. installed...