Unable to run executable (e.g. a hotfix) - "Windows cannot access the specified device, path, or file...."

 

Issue:

When trying to manually install an executable file (e.g. a hotfix) on a server, the fololowing error pops up:

 

"Windows cannot access the specified device, path, or file. You may not have the appropriate permissions to access the item"

 

 
Cause:
There are various possible causes but in this case the problem was caused by the fact that the hotfix had been downloaded on another computer and then copied onto the server. As such, the server had marked the executable as being unsafe and so blocked any attempt to run it.

Solution:
Right click on the executable and select 'Properties'. From the general tab, click on the 'unblock' option which appears under the security heading.