oCanvas.Save(Server.MapPath( doesn;t work

This line of code doesn't work in my server. I works fine in my development application.
I have 2 different Windows host servers and I get the same message:
Error Line 56:
oCanvas.Save(Server.MapPath(
 
"123.jpg"), ImageFormat.Jpeg;
 
Please help thx
Richard
 
 
 
 
 
 
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