I tried installing a program a from the internet and this resulted in some programms not running properly. For example my windows media player has a scratching sound and another program (mixcraft) cannot play sounds through my computer keyboard.
One option would be to uninstall the program that caused the issues. Another option is to use system restore to back to a restore point before you installed that program. What is the name of the program?
I agree with alphanumeric's post, that you basically have 2 choices: uninstall or system restore. Sometimes a program/app corrupts during the downloading process. You can uninstall it and then reinstall it to see if you still have the same problems after the second installation. If you decide to uninstall/reinstall, be sure that you have removed all of the program's remnants before you reinstall it. I usually do a manual Advanced Search, in which I search my whole system (rather than just the indexed locations) for any files or folders related to that program, and then delete any files or folders that are found.
If you continue to have the same problems after the reinstall, then check to see what restore points you have on your system. If you have something very recent (so you won't lose too much if you restore from that point), then you can do a System Restore.
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