ITunes new version dosent recognize my iPhone?

So I updated the new iTunes on my HP computer, I plugged in my iPhone then clicked the iTunes and it dosent connect with my iPhone for nothing lol I want to download songs and I can't because my iPhone 4 dosent connect with it somebody please help lol I already looked on youtube and it stil dose not help

Unplug the USB Cable from your computer and plug it again, should work.

RE-INSTALL ITUNES,
THATS IT.

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