What is blocking driver installation in Windows?

Question

I've written a C program in Windows that uses some precompiled files from WinDivert. My program uses a .dll from WinDivert and some of the functions in the .dll install the WinDivert.sys driver. There are also a few more files from WinDivert that are a part of this (a .lib, a .inf, and another .dll).

The problem is that on one of my computers (Windows 8.1 64 bit), everything works perfectly. But, when I try to use the program on my laptop (Windows 8.1 64), my friend's laptop (Windows 7 64), or another Windows 7 64 desktop, something blocks the installation of the driver. I'm unsure what is blocking it or how to stop it from being blocked because on all computers:

+I'm running on an admin profile

+Running the program in admin command prompt

+Tried disabling firewall, anti virus, etc (although it runs fine with these on for the computer that works)

+As far as I can tell, all my security settings are the same

+Note: the driver does have a valid signature.

Why does the driver install perfectly on one computer, but not on the other three? What could be issue?

Answer 1

The main causes for 1275 errors are documented on the WinDivert FAQ. However, there may be other causes that I'm unaware of (perhaps some experts out there can help?)

Another thing to try is the following commands:

sc stop WinDivert1.1
sc delete WinDivert1.1