This is how to FACTORY RESET your Samsung (Galaxy S) Infuse
Click Phone (green call button) type *2767*3855#
The phone will directly go to factory format.
Good luck!

Actually, that's what's called a "GSM Reset," not to be confused with either the least destructive reset, which can be achieved from within the phone; or the somewhat more destructive, actual "factory reset" achieved by holding-down the up/down volume buttons while pressing and holding the power button, as described elsewhere herein.
There are, in fact, three (3) resets, each more destructive than the one before; and the GSM Reset (the 3rd of the three) is the grandaddy of 'em all... the
big dog of resets. It returns the phone to the way it shipped from the factory... as if brand new, out of the box. Along the way, it reformats all media in the phone (all internal memory and internal SD). Obviously, then, if there's anything on the phone which the user wants, then s/he needs to back it up; and also get it off the phone (typically via a USB or WIFI connection to one's desktop/laptop PC).
If the SIM card's in the phone at the time, it sends to the AT&T system some reset data tied to both the IMEI number, and the phone number; and if the SIM card's not in the phone at the time, then it only sends IMEI-related reset information to the AT&T system; in either case, doing no damage to (or changing anything on) the SIM card.
In keeping with my personal "if it's worth doing, it's worth doing both fully and right" philosophy, I've stopped messing with any but the mondo GSM Reset. It leaves nothing to chance... returns the phone to factory state with no doubt, whatsoever, that nothing of the phone's user remains; and that nothing installed subsequent to the phone's shipping from the factory is still there and goofing things up. It's thorough, and takes no prisoners. It's the only reset worth using, as far as I'm concerned; which means, obviously, that some serious backup of data and apps needs to be performed first... my personal favorite method is using MyBackupPro, in addition to copyining SMS and contacts to the SIM card. Syncing contacts with GMAIL is also not a waste of time, just as a backup to the backup at least as far as contacts are concerned.
When the 2.3 Gingerbread upgrade is finally available for the Infuse, knowing how to do the GSM Reset will be essential for all users. For the reason, see my posting
here.
See, also, my specific Captivate reset steps
here, bearing in mind that the actual steps on the Infuse may or may not be exactly the same (I'll know after I get my Infuse, tomorrow); though the
GSM Reset is, I believe, the same on both the Captivate and the Infuse.
________________________________
Gregg DesElms
Napa, California USA
gregg at greggdeselms dot com