Black screen

[CHAVON11]

 I cleaned the keyboard with à brush  under the keys and cotton ball on top of keys now monitor is not working

[TEJ1602]

@CHAVON11, Welcome to HP Support Community!

I see that you have issues with the PC not booting up, this has nothing to do with the keyboard cleaning. 

I'd recommend you follow the steps from the document HP PCs - Computer Does Not Start to resolve the issue.

Hope this helps! Keep me posted. 

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