Hello can you help me to fix this problem my acer aspire v5 431p after i upgrade to windows 8.1 i can't use my projector i've trie to install to install the latest graphic and it won;t work it give a blurry screen. and back old version.

Change the resolution of your display and recheck the issue.

Hi,

How is the current situation?

Most likely, your projector is out of focus. You can notice that in front of the lens, there is a small Outer ring for zooming in and out. Close to that there is an inner ring that you can use the adjust the focus. Check this out and hope you can remove the blurry effect.

In addition, please refer to this article:

Projector display is fuzzy, streaky or the screen image is displaced

http://www.rm.com/support/technicalarticle.asp?cref=tec333092

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