Since it may relate to installation, I post it for any resolution.
Unable to run DWG TrueView. This may be due to one of the following:
1) This version of DWG Trueview was not installed properly. In this case, you may wish to reinstall DWG TrueView.
2) You do not have sufficient rights to run DWG TrueView.
Wherever I open a DWG files, it gives me the following message: