It's possible to reference the tables on the MDB using SQL Server Management Studio in order to determine what the character limits are for Service Desk Manager fields. See steps below:
1. Log into the server using SQL Server Management Studio.
2. Expand MDB.
3. Expand Tables.
4. Navigate to the table where the variable you're looking for is stored, and expand Columns.
5. The variables are listed here, including the maximum size available for the field.