Fixed iphone 4 screen, now it won't restore or turn on correctly (PLEASE LOOK)

Question

Ok I fixed the digitizer on my screen, and it's been like 2 weeks since it's been on and working. Anyways, I plugged it in, and after a couple of minutes it turns on, let's me unlock it, then says connect to itunes, well Itunes doesnt read the cord on any computer, and yet my charger shows its picking up the charge (99%)
When I put it into recovery and dfu mode the power button works, but not to turn on, will just flash the apple logo for a couple seconds, turn off, repeat. But Itunes does read the iphone when I put it in recovery and dfu mode but when I try to restore I get error 21
I turned off my virus protection and tried to restore like it says for error 21 and it still gives me the error
any reason that the power button doesnt turn it on but works for dfu/recovery mode? Also how do I fix error 21 (also updated to 10.5.1). I need to get this restored to work!

Answer 1

Hardware fails. It's a fact of life. It's also easy to damage sensitive electronics. If it's not a software problem, it's a hardware problem. You opened up your phone and replaced the display. It stands to reason that either whatever happened that broke the screen also damaged something else, or you inadvertantly damaged something else when you opened it up.
I fail to see how that makes Apple "money grubbing". Even Apple doesn't repair iPhones at the stores. They send them off to a facility where they have the necessary conditions and equipment to do it right.
Perhaps you should have just paid the out of warranty replacement fee and gotten a replacement phone directly from Apple. Since you opened it yourself, that option is no longer available to you.