If you are on a version of The Raiser's Edge prior to 7.82, you must upgrade to version 7.85, log into and upgrade your Raiser's Edge database to version 7.85 prior to updating to version 7.91.
To resolve your issue, complete the following steps:
1. Detach your database in the Blackbaud Management Console
2. Uninstall The Raiser's Edge version 7.91
3. Install version 7.85 of The Raiser's Edge
4. Attach your database
5. Log into and upgrade The Raiser's Edge database
6. Upgrade The Raiser's Edge to version 7.91
If you are running Vista and receive this error, refer to BB360338.