SQL Agent Job Fails when logon changed to user account

Hi,
I have a job that emails the history of all the jobs every day. That was working fine untll I changed the sql agent logon from local account to a dedicated sql server account. I can not change it back to local account because I canged it to get another xcopy job to work. How can I fix this issue?
Thanks in advance.
Madduri

Hi,
Thank you for the reply. The xcopy job is working fine but another job that executes a sp to get the history of all the jobs on the server is failing when i am using a user account for sql agent logon. the error says:
Executed as user: XYZSQLSA. Error formatting query, probably invalid parameters [SQLSTATE 42000] (Error 22050)Unable to open Step output file. The step failed.
The job works fine if I use local system account. the account i used has admin privillages on the server.
Thanks, Madduri

Finally I found the fix for my problem. It worked when I changed the logon for MSSQL SERVER Service too to the same logon account i used for SQL SERVER AGENT service.
Thanks for all your replies.
Madduri