Below are the update rollup version numbers. You can go through your import log files (%username%\AppData\Roaming\Microsoft\MSCRM\Logs\crm50dmsnapin) to identify the database
version you are trying to import.
Update Rollup 1 - 5.0.9688.1045
Update Rollup 2 - 5.0.9688.1155 -> CRM2011-Server-v2 - 5.0.9688.1157
Update Rollup 3 - 5.0.9688.1244
Update Rollup 4 - 5.0.9688.1450
Update Rollup 5 - 5.0.9688.1533
Update Rollup 6 - 5.0.9690.1992 -> has been re-released (original release version: 5.0.9689.1985)
Update Rollup 7 - 5.0.9690.2165
Update Rollup 8 - 5.0.9690.2243
Update Rollup 10 - 5.0.9690.2740 -> has been re-released (original release version: 5.0.9690.2730)
Update Rollup 11 - 5.0.9690.2835 -> partial re-released (Server: 5.0.9690.2839, Client: 5.0.9690.2838)
Critical Update for Rollup 11 - 5.0.9690.2903
Update Rollup 12 - 5.0.9690.3233 -> partial re-released (Server: 5.0.9690.3236)
Update Rollup 13 - 5.0.9690.3448
Update Rollup 14 - 5.0.9690.3557
Update Rollup 15 - 5.0.9690.3731 -> partial re-released (Client: 5.0.9690.3739)
Update Rollup 16 - 5.0.9690.3911