The process cannot access the file because it is being used by another process.

I get this error 'The process cannot access the file because it is being used by another process.' when right after I send email with file attachment.  What I am doing is send an email with file attachment and then i click a button to delete the same file from server.

I did some research and found that the asp.net process basically locks the file so cant delete it.  How do I unlock the file?  The email code I thought would release the file once the file is sent but it still holds the reference to the file I guess.  Also doesnt send method, close the mail object?

 
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