msi must be launched through set up is what i get when itry to download stuff. how do i fix this problem?

Answer 1

The msi ( Microsoft Installer ) needs to be repaired.

Go to Start/Run and type in:
msiexec /unregister [click ok]

Then Start/Run and type in:
msiexec /regserver [click ok]

If neither of the above has helped: Go to Start/Run/Regedit and navigate to:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSIServer

Does the image path in the right pane correctly point to: (modify drive letter as needed)
C:\Windows\System32\Msiexec.exe /V

If not: boot into safe mode and then go to Start/Run/CMD and type in: msiexec.exe

Once done and while still there type in: msiexec /regserver
Check the image path again, if it is now present, reboot.