sumÂ’n mightÂ’a takeÂ’n over your chm files. try this;
-Open up windows explorer
-go to [Tools]
-pick [Folder OptionsÂ…]
-then pick the [File Types] tab
-scroll down to the extension that says [CHM Compiled HTML Help file]
-then click the [Advanced] button
-under actions, click [open]
-then click [Edit] button
-the [Application used to perform action:] field should say ["C:\WINDOWS\hh.exe" %1]
sum'n else you can try is to open up dos and run [SFC /SCANNOW]