I have a job which backs up the DB & send an email using sp_send_dbmail, it's been working for months up until now. Nothing to my knowledge, no matter how I run it I receive:

"Msg 22050, Level 16, State 1, Line 0
Error formatting query, probably invalid parameters
Msg 0, Level 20, State 0, Line 0
A severe error occurred on the current command. The results, if any, should be discarded. "

By restarting the SQL Services will that fix the problem?