The dialog will only appear for customers who already have an installation of System Mechanic Ultimate Defense installed on their PC and they specifically use the download managers to attempt updating and not the in-product web update popup. It occurs because the download manager performs an install check to protect the integrity of the current installation 

How To Resolve

  1. The file does still download and can be run from its saved location by opening Windows Explorer, navigating to the folder named C:\Users\<YOURUSERACCOUNT>\AppData\Local\Temp\iolo\dm, lookin for the installation file named SystemMechanic_A50DE83F-EFEC-48D0-B4DC-3E98620FC509.exe, or similar and double-click on it to install the product.

  2. Check for updates from the product help menu by clicking on the question mark (?) at the upper-right and then Check for updates.

  3. Perform a complete uninstall of System Mechanic from Windows Control Panel and then Programs and Features and reinstall using the download manager