While scanning a disk or a folder, WinCatalog can save a log information about the scanning session.
If you experience any problems scanning a disk, please follow to the Administrative tab of the Program Options, enable the debug logging, set logging level to "Debug" and the log file location to "Desktop" or "Documents" (if you click the Explorer button next to the value field, the selected folder will be open in Explorer). Unmark "Delete log file on success" option and start the scanning session.
Then please try to add or update a disk and recreate the error, then please send the log file to us for the investigations.
To open Program Options please click the Catalog button (left from the Main tab of the Ribbon toolbar), and then click Options.