Windows saves a copy of the installation files for the 'Microsoft C++ Runtime' libraries and 'Control Expert' under the folder named 'C:\Users\Public\Downloaded Installations'. Depending on the group policy, it might not have had access rights for saving the files to the folder. If an installer related error gets returned when trying to install a newer version of 'Control Expert' on top of an older version', the issue could be due to the installer software not being able to find the necessary files required to perform the uninstallation of the older version within that folder.
The following steps can be used to resolve the issue:
- Mount the iso image for the older 'Control Expert' version.
- Run 'Setup' as an administrator.
- Select 'Remove' to uninstall 'Control Expert'.
- Open the 'Programs and Features' in the 'Control Panel'.
- Uninstall all the DTM libraries that were installed by the older 'Control Expert' version.
- Reboot.
- Mount the iso image for the newer 'Control Expert' version.
- Run 'Setup' as an administrator.
- Reboot the PC after the installation completes.
- Open 'Control Expert' to verify that there are no problems.
- Close 'Control Expert'.
- Open the 'Security Editor' and verify that it is working.