AS some Anti-Virus application sometimes can cause ACR to not open correctly it is advisable to add the ACR folder C:\ACR to your computers Anti-Virus White list. Your local tech will be able to assist you with this. If you use AVG the below instruction will assist you with adding the ACR folder to the AVG white list.
Open AVG
Click “Options” in the top corner
Click “Advanced Settings” from the drop down
Click “Exceptions”
Click “Add exception”
Change the drop down to “Folder”
Press “Browse” expand the C:\ drive and click the acr folder and press “Ok” or
Type in “C:\acr”
OK out and that should be sorted.