Hi Deadlydan,
· Did you make any software or hardware changes on your machine prior to this issue?
· Which operating system is installed on your machine?
For Windows Update issue, you may follow this link & check if it helps.
For slow performance of the computer,you may run the performance troubleshooter which checks issues that might slow down your computer's performance.
Open the Performance troubleshooter
Refer:Ways to improve your computer's performance
Hope the information helps. Please post back and let us know.
Regards
Debleena S
Microsoft Answers Support Engineer
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