Upon accessing a UNC path to a server, you may get the error:
Access to the resource ‘[UNC path]’ has been disallowed.
Typically the person will be trying to access the server share by entering the \servershare path into the address bar of an explorer window. This may be habit or convenience but it could also be due to a lack of options. The GPO setting enforcing this “problem” is one that removes the Run entry from the Start Menu.
User Configuration ->Policies -> Administrative Templates -> Start Menu and Taskbar-> Remove Run menu from Start Menu
To gain access to the server share, the above policy will have to be disabled or set to ‘not configured’. The Remove Run menu from Start Menu setting also prevents users from accessing resources in UNC paths in the address bar. See the full description below for the details, copied from Group Policy Editor:
Allows you to remove the Run command from the Start menu, Internet Explorer, and Task Manager.
If you enable this setting, the following changes occur:
(1) The Run command is removed from the Start menu.
(2) The New Task (Run) command is removed from Task Manager.
(3) The user will be blocked from entering the following into the Internet Explorer Address Bar:
— A UNC path: \<server><share>
—Accessing local drives: e.g., C:
— Accessing local folders: e.g., temp>
Also, users with extended keyboards will no longer be able to display the Run dialog box by pressing the Application key (the key with the Windows logo) + R.
If you disable or do not configure this setting, users will be able to access the Run command in the Start menu and in Task Manager and use the Internet Explorer Address Bar.
Note: This setting affects the specified interface only. It does not prevent users from using other methods to run programs.
Note: It is a requirement for third-party applications with Windows 2000 or later certification to adhere to this setting.