[Skip UAC Invalid Parameter on Windows 8 Pro x64]

I have the same problem. I have a desktop and a laptop (both with Windows 8 Pro 64-bit), but I have only just installed Windows 8 on the laptop (from a totally clean install). Both have CCleaner 3.27.1900 installed, and although CCleaner works fine on the desktop, it doesn’t on the laptop.

 

After installing CCleaner on the laptop, the UAC prompt comes up every time I open the program. Then when I go to Options > Advanced > Skip User Account Control Warning, the tick box is unchecked. If I try to tick it, an error message comes up saying ‘The task XML contains a value which is incorrectly formatted or out of range’.

 

On the desktop there’s an entry in Task Scheduler for CCleanerSkipUAC, but on the laptop there isn’t.

 

Screenshot attached:

 

I have the same problem but when I try to check the "Skip User Account Control warning" I get a  "The parameter is incorrect" message.