Microsoft Jet allows you to establish table-level validation (TLV) rules to restrict the value or type of data entered in a table. However, if you implement TLV rules in the Design Master without determining that any existing data does not violate the validation rule, you might encounter a synchronization error in the future. For example, assume that you apply a TLV rule to a field that already contains data and you then test to make sure that the existing values meet the rule. There might be new or updated records in other replica set members that do not satisfy the new rule. If you do not test the existing values in the other members and change the values that fail the rule, the next synchronization will fail to correctly update the records. When Microsoft Jet applies the new or updated records from the other member to the Design Master, Microsoft Jet tests each insertion or update against the rule. If the value fails, the update fails and an error is written to the MSysErrors table in the receiving member. To correct the error, you must correct the invalid values in the sending replica set member. You can avoid the error by synchronizing all members of the replica set with the Design Master before applying a TLV rule.