I had Nintex Workflow 2010 installed in a SharePoint 2010 environment, and I had to un-install both, then re-install SP 2010 and NW2010. When I run the NW2010 installer, the WSSHelper.exe displays that there was an error checking the license, and asking if the account is a SharePoint Adminstrator (which it is), then when I hit a key to continue, I get a dialog box that "there is a problem with this Windows Installer package. A program run as part of the setup did not finish as expected. Contact your support personnel or package vendor." I checked the assembly, and the Nintex .dlls are still present in the C:\Windows\assembly, and I checked the modified dates on the .dlls, and they are from the previous install. Could this be causing my installation issues? Would removing the .dlls correct the problem?
EDIT: I ran the installer through the command prompt as an administrator, and it worked.