trouble with the appstore

Hello, i have a trouble with the appstore when i type anything in "Search" the appstore dis, i tried the apptroubleshooter then i receive this and it's can't help anything ~~
i also install or update apps normal just can't use the "Search"

In the elevated command prompt type sfc /scannow and return. It should fix any corrupt system files.

it's said that i'm must be administrator and my acc is the only on my laptop ~~

Windows Key + X and select Command Prompt (Admin), now you can run the sfc command

i see the problem now, i using win 10 technical preview, after i run that sfc and restart my lap the watermark apear on my screen and the problem in appstore fixed, after i used tool to remove the watermark the problem in appstore comeback again ~~ i think it remove some file that afect to appstore

Thanks u, i'm tried another tool to remove the watermark and now it's ok.

Glad it's OK now