Hi, i have a Samsung S3 (GT-i9305) stuck on opening screen.

[Android Central Question]

This started a short while ago, i had to turn my phone off and back on again for it to boot up.. NOW its just stuck on this screen.. it doesn't do anything at all.
All i see i see is Samsung Galaxy SIII GT-I9305, it wont move from there. I have read some fixes like hold the power button, volume up and home button to go into a fix screen, all i get then is jargon with a robot on the front screen with tiny writing up the left of screen, and below os "Downloading.... Do not turn off target!!. Its not downloading anything.. its was stuck on this all day yesterday. In the end i just turned it off. Tried again today.. same thing.
Anyone have any other fixes.. the ones on google arnt working..

 

[belodion]

You booted into Download mode, whereas you need to boot into Recovery to try a Cache Partition wipe or Factory Reset. I don't know how that's done on a Samsung, but in any case I doubt that either wiping or resetting would help. There may be hardware failure, battery failure, or software failure. You could try reflashing the stock firmware.

 

[Rukbat]

Recovery is Volume Up/Home/Power, the "jargon with a robot on the front screen with tiny writing up the left of screen", which says that you have no Android on the phone (or at least no boot.img file) and no recovery. I'm guessing, based on experience, that all your apps, pictures, music, etc., is also gone, so if you didn't keep the phone backed up, you lost it all.

You need to reflash the ROM - see [Samsung] How to flash Stock ROM via ODIN. (Assuming the phone still works - no hardware failure - all that you need is free, so it's worth the try. [Any apps you paid for on the Play store will still be free, as long as you put in the same Google account once you've fixed the phone.])

If there's a hardware problem, you'll need to pay a shop for a new motherboard, and a new i9305 (or a newer, better phone) will cost less than the repair.

 

[B. Diddy]

Welcome to Android Central! Here are the exact steps for booting into Recovery: [Guide] Rebooting into Recovery Mode for the Galaxy S2, S3, and Tab2. - Android Forums at AndroidCentral.com. If you're able to get there, try wiping the cache partition. If that doesn't work, then see if you can do a factory reset from that menu. If you can't, then as Rukbat mentioned, it could be firmware corruption or hardware failure.