This error occurs because there is a problem with the Share Point content database, which prevents Sharegate from copying.
In most cases, the problem is simply that the database has run out of free space.
If the issue happens in all the lists created within a site collection (even in new ones that you create), then the site column is corrupted, as well as the column in all the lists.
This can be fixed by running one of the following Power Shell scripts to update the columns and correct them: DISCLAIMER: Always perform a full backup of your Share Point farm before running any of these scripts.
If your error is not listed here, you can check Windows Installer Error Messages on the Microsoft site.
See Error 1327 | "Invalid Drive" | Install | CS4, CS5, Acrobat, Reader.
Like most Windows applications, Acrobat and Reader use Microsoft Windows Installer technology for installing updates.
If the update fails, you can get one of the following Microsoft Installer errors. Adobe updates the list as it learns more solutions to common errors.
This means that the "Modified By" column is corrupted, either in the site collection or only in the list.
If the issue happens with only one list, then the column is only corrupted in this list.
Alternative solution: This error sometimes appears when a drive is mapped for the user and the installer is running in a system context.