In order to install Bitdefender Security on systems with Windows 7 Service Pack 1 and Windows 8, several Microsoft Knowledge Base packages need to be present on the device.
You can install them via Windows Update or manually install those specific packages.
Install using Windows Update
Press the Windows Start button 
| 
in the lower-left corner of the screen. In the search box, type Update and then select either Windows Update or Check for updates in the list of search results.
Make sure your device is updated.
Manual install
- Download and install KB3140245 on Windows 7 – https://catalog.s.download.windowsupdate.com/c/msdownload/update/software/updt/2016/04/windows6.1-kb3140245-x86_cdafb409afbe28db07e2254f40047774a0654f18.msu
- Download and install KB3140245 on Windows 8 – https://catalog.s.download.windowsupdate.com/c/msdownload/update/software/updt/2016/04/windows8-rt-kb3140245-x86_d68690bf0bc828ea9368a6e25dc6a9b1b3adf151.msu
NOTE: If you are using an older version of Windows 7 and the package above cannot be installed, you can find the proper installation packages here.