Question about NIS installation

NIS 2013
PC-Vista home premium SP2
IE 8 browser

This is partly related to a question I posted elsewhere, put would like to post this part separate

If for some reason some windows files were corrupted (not infected)-
1. Would NIS be messed up if it was already installed prior to window files corruption?

2. If NIS were affected by windows file corruption, would that be reflected by NIS showing a red X in the NIS tray icon?

3. If auto fix shows no problems, would it be safe to say NIS is not affected by any corrupted windows file?