You may found an error while posting inventory journal (Inventory Counting, Inventory Transfer etc.) if you enable ModifiedDateTime property on InventJournalTrans or Inventory journal related tables. It throws following error.

The operation cannot be completed, since the record was not selected for update. Remember TTSBEGIN/TTSCOMMIT as well as the FORUPDATE clause.

 It should not throw error if it's only standard code and no customization is there. But the reason of this type of error is that somewhere update on record has been performed without selecting for forupdate clause or without locking the table. best way to know put a break point in info class and debug.
There no single change in set the InventjournalTrans table ( I am not sure it was InventJournalTrans or inventTransPosting ) property ModifiedDateTime as YES and from one blog you can got the clue that It may happening because of this property. After removing this property it may work fine.

apparently it should not happen in standard code. even then click on the error details. it will take you to some class. in that class find TTSBEGIN and Select Keyword. Do remember TTSBEGIN always accompined by TTTSCOMMIT. so find any TTSBEGIN with Missing TTSCIMMIT, Put there TTSCOMMIT And after SELECT write "forupdate"