Open Windows Explorer, locate the folder with your web site, right-click the folder and display its Properties. Choose the Security tab.
Click Add... The Select Users, Computers and Groups dialog appears.
Click Locations... and choose your local computer:
Click OK. Enter network service into the box and click Check Names. The name should be resolved to NETWORK SERVICE.
Click OK. The account is added to the list of accounts. Grant the account with Modify permissions and click OK.
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