Fixing windows 7 errors & Windows 7 troubleshooting can be a tough job if you don't know where to start. Fortunately, there are some simple, tried and true methods that you can do to repair Windows 7 errors quickly and painlessly.
Reboot your system: Sometimes all it takes is a simple reboot to make your problem go away. In some cases, we need to hit F8 during booting and pick "Last Known Good Configuration" if facing trouble starting up your machine. Make sure to save all your work and unplug all unnecessary peripherals before rebooting.
Do a System Restore: Windows' System Restore can also use to wipe out any nasty changes that have happened in your PC. If the restore point saved on your computer has been a while back, which may happen if system does not regularly create restore points, anyone may lose a bit of data with this tool.
Clean your registry: The previous two methods, although very thorough, might remove a huge chunk of important information from your computer’s widows 7 support. The easiest method then is to just run a registry cleaner that will tidy up system registry to remove incorrect entries and other possible errors.