I'm having a bit of a problem with a client and I'm at my wit's end for the cause. The client has a CRA/monitor who wanted to try doing some data entry so that he would be able to offer sites any help from first-hand experience. I gave him access to a test system mirror of the production system and every time he tries to enter data on a CRF with a date field (which is most of them) he gets an error that the data entered is not in the proper DD-MMM-YYYY format. he gets this error even if the date is in the proper format, or if the field is blank, and none of the date fields get the red highlight an exclamation mark that usually accompany these error messages. He's the only user I've had report this problem and I can't recreate it myself. It happens on every browser he's tried, but not on a different machine.
Can anybody help me figure out what other kind of client-side issue could cause this?