iPhone 4S restore problem

Hi

Earlier this week I tried to sync my iPhone up to a new laptop. iTunes told me it would wipe the data on the phone and sync the new stuff over but then said that there wasn't enough space on the phone to sync, so I decided to restore it and then re sync. There was clearly some issue as it was restoring as it is now stuck permanently on the 'connect to iTunes' screen. Connecting it to iTunes and clicking restore sometimes gives the 3004 error but changing the host file fixes this. Then, when iTunes has finished extracting software the iphone reboots and the message 'This device could not be found' appears in iTunes, cancelling the restore.

Has anybody got any suggestions?

The iPhone has never been jailbroken but I tried using tinyumbrella as ive seen a few forums suggest it. However, I wasn't able to find how to do this with the newest version of tinyumbrella so downloaded the 7.12.00 version. When I connect the iPhone tinyumbrella recognizes it but says 'this device is not connected'. When I click exit recovery my iPhone restarts but still comes up with the 'connect to iTunes' screen and a new device number is listed in tinyumbrella.

When the iPhone restarts to restore it comes up with the apple logo and a loading bar but then the error 0xE800084 appears in iTunes. The loading screen remains on the iPhone till I turn it off and on

OK I have made some progress. The restoring loading bar on my iPhone now progresses about 5/10% into the 'restoring iPhone software' in iTunes. The phone then disconnects itself and the restore progress is lost, returning me to the 'connect to iTunes' screen. Any ideas?