So let’s say you have a Microsoft Access Database file, which you need to have 5 employees working on, at the same time. A great way to achieve it, is by creating a network drive, or in my case – shared folder.
In our office, we use Microsoft Access to manage our PO (purchase orders) system. We have 5 employees putting data in. The file itself is located on a “server” which is basically a local machine with Windows 7 premium installed. It has a shared folder, and they all work on this Microsoft Access Database (using Access “shared” open mode).
For 4 of the 5 employees everything goes pretty smoothly. One employee encountered a problem, where while trying to open the file – while others were using it – he got the following error:
“Open File – Security Warning: We can’t verify who created this file. Are you sure you want to open this file?”

The Solution
The problem here, is that the user is trying to open a file which is not located on the local drive. Windows thinks that the file is not safe (an intranet location) and tries to block it.
In order to resolve it, all we need to do is add the file’s location to the “trusted area”/ “safe zone”. To do that, follow these steps:
1. Open Control Panel, and go to “Internet Options”.
2. Click on the “Security” tab.
3. Click on “Local Intranet”.
4. Click on “Sites”.
5. Click on “Advanced”.
6. Click on “Add”.
7. Type in the shared folder address where the file is, for example \\home-pc\users\admin\documents\.
8. Click “Add”.
9. Click “Close” and then “OK”.
10. Try to open the file again, and you will be rid of the security warning.