Hello Alex,
Thank you for your message.
Probably the folder was somehow deleted by antivirus software or some cleaning tool. Please try completely uninstalling the Viewer by following
this tutorial and then
install it from scratch.
Before you do that though, export your address book so that you could import all your remote PC records back into the Viewer.
In addition, I highly recommend that you add the Viewer installation folder and Remote Utilities Files folder to antivirus software exceptions list to avoid future problems in this regard.
Hope that helps.