It's also possible this error is because there was a previous installation of Adobe Acrobat 7 on the computer and even though it was uninstalled, there is still a residual Acrobat 7.0 folder in Program Files (i.e., that wasn't deleted during the uninstall). This old folder has the demon permission settings in question.
In that case, select a different location for it to be installed: That is, during the installation sequence, select a "Custom" install (instead of a"Typical" or "Complete.") Then specify a different target folder such as C:\Program Files\Adobe2.