So my laptop which is an MSI GT70 recently ran into some issues, when turning it on one day I noticed the default graphics card has changed into the Intel HD integrated graphics, I went into device manager and noticed that the GTX 780M has changed to Uknown Device, I have tried doing update driver software, but it only comes up as Access Is denied on the window. Same thing goes to installing the new Nvidia Drivers, It would just say in the nvidia driver window that the graphics installation has failed, doing a system restore also hasn't done anything, just come's up as the same thing. Uninstalling and re installing the drivers also has no effect. Disabling anti-virus and firewall has no effect either.