Metro app weather says it can't run if uac is off. Don't know why Win 8 started giving that message, although I did have uac control off. Is there a fix other than having uac on.
Most metro apps will not work with UAC turned off. There is no fix, other than turning UAC on. The reason is that Metro uses UAC's virtualization features (among other things) and without it, they just can't function.