SQL database error

I have client getting this message on her computer im not to cluey on ms access so im asking you guys

Error:

OBDC–call failed.

[microsoft][obdc sql server driver] sql server]Cannot insert the value NULL into column ‘ModifiedDate’, table ‘Coursebooking.dbo.course’; coulumn does not allow nulls. INSERT fails. (#515) [microsoft][obdc sql server driver][dql server] the statement has been terminated. (#3621)