Often caused by the table on the server having a Primary Key field of a
DataType that Access has no *exact* equivalent for.  BigInt for example.  If
rounding or other mis-interpretation of the PK value occurs this can look to
Access like the record has been edited or deleted when that is not actually
the case.

Sometimes these things happen only in datasheet view of a link.  In forms
and reports you might not have the problem.  Passthrough queries in my
experience do not do this.

Also a good idea to add a binary Timestamp column to the table on the server
and re-create the link.  That column is then used for dirty record tests
instead of real data fields and that solves many Access - SQL Server
problems.