There is a character limit of 254 in a Raiser's Edge field.
In Sphere, it is possible for Custom Fields to have a character limit larger than 254, which causes the error to occur.

Note : Before you proceed with the following instructions, back up the database. If your organization integrates multiple Blackbaud products, refer to the Additional Requirements section of the backup article.

The following script can be run on 2005 or 2008 SQL to resolve the error message:
1. Go to Start > All Programs > Microsoft SQL Server 2005 > SQL Server Management Studio on your server.
2. Select Raiser’s Edge database.
3. Click New Query.
4. Add Command:
UPDATE BatchData SET data = LEFT(data, 255) WHERE LEN(data) > 255
5. Click execute (in the SQL screen).