My apologies if this thread is redundant. I've been on a monotonous search for a fix in other threads and have found that no other posters are experiencing the exact same situation as I am. If a similar thread has already been created/discussed, please point me in the right direction! Problem: Cannot un-jailbreak iPhone and then Upgrade to iOS 5.1 Phone Specs: iPhone 4S, currently jailbroken (via redsn0w), iOS 5.0.1 Error message: "The iPhone **** cannot be restored at this time because the iPhone software update server could not be contacted or is temporarily unavailable." I've been attempting to un-jailbreak and then update my iPhone 4S to iOS 5.1 for the past 28 hours or so. At first, I took this error message as though the Apple server was overloaded. I waited some time, tried again - same error message. First attempts were made while at work, connected via Ethernet. I followed advice that said to flush my laptop's DNS cache - no luck. I attempted to update over the air, through my iPhone specifically - no luck. Attempted restoring through iTunes - same error message. Downloaded the .ipsw (tried both 5.0.1 and 5.1 .ipsw's) and tried to manually restore - same error message. I then assumed that my network at work had a firewall, so I attempted all of this again at home (both through iTunes and over the air, through iTunes and manually)... Still to no avail and always received the same error message. I've reset my network settings on my iPhone, have tried setting my DNS server on both my phone and laptop to google's public DNS (184.108.40.206) and then OpenDNS (220.127.116.11) and it still didn't work in any of those scenarios. I've checked my host files in the Terminal app and everything seems to be written fine... Please see below for what my host file looks like, and let me know if there is something that should be changed: 127.0.0.1 localhost 255.255.255.255 broadcasthost ::1 localhost fe80::1%lo0 localhost The last one looks a little funky, but I can't seem to find any other threads that explain any localhost address that's similar to this. Therefore, I don't know if that needs to be changed or not. If there's anyone that can send along advice or realizes what I'm doing incorrectly, I'd really appreciate the insight! Just an FYI... I'm not trying to un-jailbreak and update to iOS 5.1 for any reason in particular. Having my phone jailbroken just isn't essential for me, and I'd really like to revert back to normal iPhone settings for a little while. All help is welcome!