How to change the default ASP.NET account used by ASPNET ?

Hy folks  

 While uploading files to a remote server using uploadfiles control, the default asp.net user account, does not have network permissions by default.

How can I give  the account such permissions ?

I need it to avoid, having to suply  user name an password to gain permission to complete the upload process

 

thanks in advance 

 

 

 
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