If you do the repair install, there is a very good chance that you will be up and running again. Run it several times.
Give this easy solution a try, as already suggested. It will not affect any personal documents. Repair Install
If you want you can try this, first. Type cmd in start, do not hit enter. Right click on CMD and then run as administrator. In cmd type sfc /scannow. Run that several times if errors are found. We will get you up and running, again.