Hey please help me! my friend shipped me a phone that was his and when i gotten the iphone i went through settings and deleted all the information off of it! and when i plugg it to my computer it doesnt show up also i cant restore any back up files because the iphone was his. and i dont have his back up files ...ever since i erased my back up files on the iphone its been stuck in recovery mode i thnk (because it shows the ipod usb and an arrow pointing up to the itunes symbol!

can someone help me get out of this problem please

This is a pretty common problem. The "erase all content and settings" option does exactly what it says. However 99.999% of the time the user doesn't read/understand the warnings and ends up with a phone that has everything erased, including the operating system.

You probably can't recover any data from the phone - if you still want to try, there are threads explaining how to boot from a ramdisk and try to recover data.

Your only option is to restore the phone. Depending on what model of phone it is, you might find that without a saved SHSH, your only option is to restore to iOS 4.2.1 (which may break your chance of unlock and untethered jailbreak)

Search around on the forum. The answers are there already regarding how to resolve this. You just need to identify basic information like - iPhone model, old/new bootrom (3GS only), do you need to jailbreak/unlock?, What SHSH did you save for the device (check with TinyUmbrella)

Prior to erase all content/settings:
what OS was installed
Was it jailbroken? If so what tool was used to jailbreak?

Thread closed. This has been asked and answered hundreds of times previously.