Thanks for posting your question on Justanswer.com, a global paid independent support site.My Name is ***** ***** I will be assisting you today.This problem is caused due to pressing some wrong key combination, try the steps below to increase the brightness.
Power off the computer.
Power on the computer
As soon as you see tLenovoevo logo starts increasing the brightness by pressing the brightness key.
If this steps fail then, Try using the intel graphics driver from lenovo site or from the d drive of your hard drive.http://support.lenovo.com/en_US/downloads/detail.page?DocID=DS031547
Hello and thank you for your question. Please let me know if you still require assistance and I would be happy to help you
Hello! My name is*****I am a certified computer professional who will assist you.If the brightness problem is still there, you can solve it by installing the Intel graphics card drivers available on the Lenovo P400 drivers webpage. See this link:
Let me know if this solved the problem, and if you require further assistance.Best regards,IT Miro
Hello again!I am following up with you to see if you require further assistance. Let me know by sending me a reply below.Thanks,IT Miro
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