A customer may lock Sage CRM for customisation using the option available under Administration | System | Lock System. If they encounter difficulties with the password of the user who created the lock, they may be unable to log back into Sage CRM.
Running the following SQL will unlock the instance of Sage CRM:
update Custom_SysParams set Parm_Value = null where Parm_Name = N'SysLockedByUsrID'
update Custom_SysParams set Parm_Value = null where Parm_Name = N'SysLockedTime'
Once done, an IIS reset will need to be carried out.
A related issue may arise whereby the system remains locked even though the above entries have been nulled. This can be caused by a duplicate entry for the MetadataVersion entry on the CustomSysparams table. You can identify whether the issue exists by running the following:
select Parm_Name, Parm_Value, Parm_id, Parm_Deleted, Parm_UpdatedDate
where Parm_Name in (N'SysLockedByUsrID', N'SysLockedTime', N'MetadataVersion')
order by Parm_Name asc
If two entries are returned for MetadataVersion, then one will need to be deleted. This can be done by deleting one of the entries using the Parm_Id column as the unique identifier, then carrying out an IIS reset. Which parameter is deleted is not especially important for the core Sage CRM product, though other components (such as custom integrations) may be dependent on the MetadataVersion value. As such, it is likely a good idea to delete the entry with the lowest value, should they differ.