When you update you iOS, have you seen this error message: not eligible for this build? The serial

Question

Dear Mr. Jobs,
My husband has been an avid supporter of Apple, having purchased a great deal from you over the past many years. Personally, I have been an iPhone user since it was introduced a few years ago. 
In July 2010, I stood in line at the Apple Store in the Stanford Shopping Center to purchase the iPhone 4. In February of this year, I tried to update the iPhone and got the 'sign of death'. My iPhone turned into a piece of brick and I was not able to make any phone calls, which at that time, was very inconvenient. I remember having to coordinate a pick up at the airport early the next morning and my phone was dead. Apparently, in trying to update the phone, it corrupted the firmware and I could no longer activate that phone. It was a frustrating experience on the eve that I had to go to the airport and I spent hours trying to see if there is anything that I could do to get the phone back in working order.
The following day, I made an appointment with the genius and my husband and I took the iPhone to the Stanford Apple Store to see if there was a problem with the phone. Without hesitation, we were asked if we purchased the phone overseas. Of course, as Asians, they probably thought that we purchased it in the black market in China. After hearing our response, their next question was whether we hacked the phone. Why would they bring up these issues? Rather than immediately delving into the problem, we found it very annoying that the employees would tried to divert Apple's problem to us. After trying to diagnose the problem, they gave us a new phone and activated it using their in-store computer. 
We took the phone home, thinking that the problem had been solved. When we got home, we tried to update the iPhone to no avail. The firmware was corrupted and we had to once again, bring the phone back to the Apple Store in the Oakridge Mall in San Jose. The Apple employee told my husband to go to the AT&T store, as there was potentially a SIM problem. My husband went to the AT&T Store and was told that they couldn't help him, as the SIM was fine. They did, however, replace the SIM so that there would be no issue.
In April, when there was an upgrade to the iPhone software, we once again tried to update the software and was unable to. Once again, the firmware was corrupted and we were forced to take the phone back to the Stanford store. Again, they asked us if we purchased the phone overseas. Why? They could have easily looked at the records, but no, your records are so bad that you are unable to pull it up. That afternoon, we spent four hours at the store, updating the OS on the computer as well as updating the iPhone. They assured us that they solved the problem.
This past weekend, as there was another update to the iPhone software, we were once again unable to update it and were forced to take it back to Apple. Again, we were asked, did you buy the phone overseas. It's very frustrating and annoying to repeatedly get asked that question. After a series of back and forth communications between the genius and my husband, we were told that they didn't know what the problem was. This time, we told them that we would not be leaving the store until they solved the problem. We have an Apple computer and an Apple iPhone, so 'Apple' should find the source of the problem and fix it once and for all. The genius then suggested that we migrate the data from my computer to my husband's computer and try to update the phone using my husband's computer. We didn't accept that answer. 
Our genius then asked the help of a second genius and after taking his suggestion, they found that the serial number for my iPhone had been assigned to France Telecom. Once again, they asked if we bought the phone overseas. Why? Please train your employees to not accuse the customers of doing this. Many of us are honest and we take offense to this. In fact, we told them that we purchased the phone from the Stanford Store (where we were at). After looking for the record, they said that we must not have purchased it from them. The onus, then, was up to us to prove that the phone was, in fact, purchased from the Stanford Store. Fortunately, my husband saved the email and was able to show the genius that the phone was purchased from them. How could your records be so poor as not to be able to find our purchase?
After two hours at the store, we were told that we, not Apple Stanford, had to call customer care to resolve the problem. Being that this is an Apple problem, I would have expected Apple to follow up on our behalf. Why is it that the customer has to spend additional time to deal with an issue that was caused by Apple. 
My husband has been dealing with customer care, who apparently has escalated the problem to other divisions within the organization. It's been two days and the problem still has not been resolved. In fact, the answer remains that they are not sure how to resolve the problem. Why can't you update your system and redo the record so that I can go on in peace. Every time I try to update the software, I'm afraid that I won't have a working phone. Do you blame me? 
This has been one of the worst experiences that I have had with an Apple product and it still is not over. Collectively, my husband and I have spent over 25 hours dealing with this issue both at home and at various Apple Stores. It has been a hassle having to go from place to place, having to sync the phone multiple times, having to update the software multiple times on both the computer and iPhone and ultimately, not having it fixed once and for all. Please let me know how you expect to compensate us for this experience and how and when you expect to fix my iPhone issues.
Mr. Jobs, I know that you expect perfection from your team. This has been a tremendous waste of time for my husband and me and has been a less than stellar experience.
Regards,
Lea Anne Ng

Answer 1

With that one, I'd check on your Hosts file on your PC, Lea.
Follow iTunes: Advanced iTunes Store troubleshooting to edit the hosts file or revert to default on Windows. See section "Blocked by configuration: (Mac OS X/Windows) > Rebuild network information".