During an upgrade, if the copy and paste of the application files is failing because a file is already in use, please check to see if any users are currently logged in.
Click on View Logins/System Shutdown..
Clicking the Show Log button will display a list of users who are currently connected to the application.
The administrator can click the Activate System Maintenance button to disconnect all users with a 3 minute warning.
During a System Maintenance period, no users other than System Managers will be able to log into the applications.
When System Maintenance is activated you will receive the following confirmation prompt
Within 30 seconds, all users who are still logged in to the application will see an windows prompt on the foreground of their screen
As the administrator, leave this on screen prompt open, let the countdown timer expire, wait 30 seconds, and then try to copy and paste the upgrade files once again.
After successfully upgrading when you log back into the application the System Maintenance will still be active, you will only have 3 minutes to diffuse your bomb (James Bond style), until all users will be forcibly logged off again.
To Cancel System Maintenance return to the View Logins / System Shutdown window and click the Deactivate System Maintenance button.
If the system still refuses to allow you to paste / overwrite the files:
Check to make sure you unblocked the zip folder when you downloaded it from the net (Highlight/select the folder, right-click and select "File Properties" and click or checkmark "Unblock" on the General tab and hit apply/OK). Then recopy the files.
Check for File Locks on your file server, force close any Dynamic Budgets related files, (sometimes windows or Terminal Services sessions will disconnect unexpectedly and leave the system thinking there is still an active connection with the file)
(Guide on how to unlock files on Windows Server 2008) or in Windows Server 2012 or later its now found in (Computer Management > System Tools > Shared Folders > Open Files)