SAP Message 60601 - Error during blocking of apportionment units for RU & &

Diagnosis
When a user is processing a rental agreement, all rental agreementswhich also belong to that rental unit are blocked for other users. Thisalso applies to the apportionment unit data.

System Response
A system error occurred during the blocking activity. A blocked cannotbe set (table VIMI08).

Procedure
Inform your system administrator of the error number.