Windows UAC feature on Windows 7 is not supported by the Critical System Protection agent with the UAC protection feature in the current release.
If both security features are enable on Windows 7, users other than the Administrator user will be restricted from performing many actions which requires UAC privilege elevation, such as opening of task scheduler, resource monitor, joining domain or any operation that marked with a shield icon in the user interface. Responses may vary from error messages to no response at all. Being part of Administrators group is not sufficient in this case and Critical System Protection system tools will not work without additional permissions being granted.
Windows UAC and the prevention feature of Critical System Protection agent both provide security features which are in conflict with each other. This conflict exists only if the prevention feature of Critical System Protection is enabled and only on Window 7. If you install Critical System Protection with the detection feature only this issue does not apply.
The two works arounds available at this time are to either:
Symantec Critical System Protection version: 5.2.9