Support for Windows 8.1?

what is your error? I run it on windows 8.1

When updating, I get an error saying that the install for either case fails and that I should check my running processes, even though there is nothing that should affect it. It started happening right about when the newest Windows 8.1 update came out.

I am not able to install content updates or marketplace content, even after doing several reinstalls and various updates and compatibility fix attempts.

Hello,

Thank you for your report. We were not able to investigate this on the engine version you reported, but there have been many version changes to UE4 since this question was first posted. With a new version of the Engine comes new fixes and it is possible that this issue has changed or may no longer occur. Due to timetable of when this issue was first posted, we are marking this post as resolved for tracking purposes.

If you are still experiencing the issue you reported in the current engine version, then please respond to this message with additional information and we will investigate as soon as possible. If you are experiencing a similar, but different issue at this time, please submit a new report for it.

Thank you.