Do a search on the forums for "1935". The common theme seems to be it is related to .Net frameworks and that they may need to be updated.
Since it is not simple to reinstall only .net framework on W7 (it is part of the operating system),
I checked the .net framework with the .NET FRAMEWORK VERIFICATION TOOL
Verification succeeded for .net 2.0,3.0 and 3.5.
Since there are more problems on this pc. (1:windows update problems with strange errorcodes, 2:unable to turn windows features on/of)
i decided to rerun the W7 setup.
i selected the upgrade option , assuming this would update corrupted files, and it did.
After that LV9 installed without problems.