ih8sn0w has released the iREB R5, RC4, RC3 for iOS 5.0.1, iOS 5, iOS 4.3.3, 4.3.x, 4.2.1, 4.x.x to fix following iTunes errors: 1604, 1601, 1600, 16xx etc while restoring custom iOS 5.0.1, 5.0, 4.3.3, 4.3.x, iOS 4.2.1 or 4.x.x firmware. You can download iREB (all versions) from below.
iREB R6, R5, RC4, iReb RC3 puts you iPhone, iPad and iPod Touch into jailbreak mode, thus helps in bypassing iTunes error 1604, 1600, 1601 or 16xx. iREB RC3 also fixes the “Waiting for iBSS” issue with iPhone 3G.
iREB R5 Supports
iREB (latest version) is available for both the Windows and Mac and can be downloaded from below. It requires iTunes 10 or later.