[iMore Question]

it wont boot up after i reset factory setting. it just appeared w/ apple logo and line circulating. please help me.

[Just_Me_D]

1. Connect the iPhone to your computer
2. Initiate the computer's iTunes app.
3. When iTunes recognizes your iPhone, select "restore". (I hope you have a recent backup, by the way)
4. When iTunes finishes restoring your device, either set it up as new or select to restore from a previous backup.

[jonister52]

I already back up my phone. do I need to download again the ipsw file for 8.4 restore? since in have already file saved in my desktop.

[Deanig_12]

Itsnshould just say restore when you launch itunes

[Just_Me_D]

I already back up my phone. do I need to download again the ipsw file for 8.4 restore? since in have already file saved in my desktop.

Unless you think you have a corrupted download, your current .ipsw file should be sufficient. If you selected to erase all contents and settings from a jailbroken iPhone then it is going to take you several attempts to restore before you're finally successful. Sometimes, all it takes is a reboot of your iPhone, Wi-Fi router and your Cable/DSL modem. Just keep trying. It'll take eventually.