I use teamviewer, and I've had that issue a couple of times. But, unattended access is the core of my Remote Support Plan. If they uninstall it, they have to re-install from the website BY THEMSELVES. If they can't manage that, no problem, it's time to schedule AN ONSITE SERVICE CALL. I no longer do any phone support without looking at the computer directly, and I let them know that from the start. I've also had them change the password, which locks me out. No problem, but that rules out unattended problem fixes, especially AFTER THE WORK WEEK, NO WORK ON SATURDAY OR SUNDAY. They learn. Either way, it's a win!