Database issues are the most frequent cause of this crash, especially if the error occurs when entering Manage Mode Rename the Database Folder
The error message "ACDSee Ultimate has encountered a system error and will close now" Database issues are the most frequent cause of
A corrupted database is a frequent culprit, especially if the crash occurs when switching to Manage mode. : If you can access the menu, go to Tools > Database > Optimize Database Reset the Database : Navigate to your catalog folder (typically %LocalAppData%\ACD Systems\Catalogs\ ) and rename the active folder (e.g., ) to something like 180Ult_OLD ) to something like 180Ult_OLD