Software requiring admin rights to install

[Slickone]

What determines if a particular application requires an admin to install or not? I've had some basic apps, even browser plugins that won't install without admin rights, yet have been able to install apps that are more complex and potentially dangerous, without admin rights. Is this not something set by the programmer?

 

[bersl2]

If you have a function that needs to make a privileged syscall, you will need to have super-user rights to execute that syscall successfully.

In the case of Windows, it usually comes from a program's using old functions.

 

[Slickone]

And this can occur during an install?

 

[MrChad]

Here's a basic, high-level guide

Most legacy apps get in trouble trying to A) write an entry to the HKEY_LOCAL_MACHINE tree in the registry or B) write or modify file in the Windows system32 folder.