MS SQL Bug: kan ikke opdatere rækker

Lige pludselig er det blevet  umuligt at opdatere/indsætte rækker via Microsoft SQL Server management Studio i vores MS SQL 2005 Jeg får to beskeder:

"Data has changed since the Results pane was last retrieved. Do you want to save your changes now?
(Optimistic Concurrency Control Error)
Click Yes to commit your changes to database anyway.
Click No to discard your change and retrieve the current data for this row.
Click Cancel to continue editing."

og

"No row was updated.
The data in row X was not committed.
Error Source: Microsoft.VisualStudio.DataTools.
Error Message: The row value(s) updated or deleted either do not make the row unique or they alter multiple rows(N rows).
Correct the errors and retry or press ESC to cancel the change(s)." 

Jeg har fundet følgende artikel: http://support.microsoft.com/kb/925719

som nogenlunde beskriver mit problem - men for mig er det alle databaser og alle tabeller (uanset felter, primære nøgler mv.)

Nogen der har oplevet dette?