[Gamer_Z]

Well Blacklite so instead of doing some research on
"DLL INJECTION"
you just gave administrator rights to the program... very stupid.

Tip:
- Install into ApplicationData folder (ALL windows versions from Windows NT and above have one) - no admin rights needed
- Inform the players that they must not run gta sa as administrator or sa-mp as admin because it's not gonna change anything. SA-MP uses since short the My Documents directory whilst GTA SA did always. So no need for administrator rights
- Make a launcher in the AppData dir which launches sa-mp server browser, and in the background it waits to let the process of gta_sa.exe appear, if it appears inject your DLL.
- Sounds like it's too much work for you, because you don't need to be smart to come up with the above points.

Make the installer give you friendly user options like install it only for me or install for everyone (while this yes, requires administrator rights), then add an option to select if the user wishes to download automatic updates without users knowledge, or notify the player before doing anything (downloading, installing).

So if all those possibilitys are there you chose the worst options, so it's suspicious.