@Aldega...
I've often mentioned to "give the Root Folder full permissions", in other posts before... quite simply; C:\ Program Files (on Vista/ 7/ 8 ) is protected - install to a folder outside of the program files for an easier time of things
The 7b error usually comes up as something mismatched, filewise, between the 64bit and 32 bit system folder, with the culprit likely being one of those pesky msvcr (?) dll thingies. Try to obtain and run an app named Dependency Walker for further clues