This device ins't eligible for the requested build

Question

Tried to install iOS 7 but my itunes keeps writing that "the device isn't eligible with the current build, at the same time i cannot restore to an older iOS tried both iOS 6 and iOS 6.0.2, i have an iphone 5, please help me im completely lost

Answer 1

clear host file  go to youtube for instruction  if your having issue  search for error 3194  .then put it on dfu  mode and if ios 7 is already available on your area you have to download it but you have to clear the .ipsw file on the app data folder and try updating again make sure you got the latest itunes .. note app dat a folder can ve viewed if you  unhid hidden folders on the control panel  ....
directory for ipsw on all os
Mac OS X
iPhone
~/Library/iTunes/iPhone Software Updates
iPad
~/Library/iTunes/iPad Software Updates
iPod touch
~/Library/iTunes/iPod Software Updates
Note: The tilde "~" represents your Home directory.
Windows XP
iPhone
C:\Documents and Settings\[username]\Application Data\Apple Computer\iTunes\iPhone Software Updates
iPad
C:\Documents and Settings\[username]\Application Data\Apple Computer\iTunes\iPad Software Updates
iPod touch
C:\Documents and Settings\[username]\Application Data\Apple Computer\iTunes\iPod Software Updates
Note: To quickly access the Application Data folder, choose Start > Run. Type %appdata% and click OK.
Windows Vista, 7, and 8
iPhone
C:\Users\[username]\AppData\Roaming\Apple Computer\iTunes\iPhone Software Updates
iPad
C:\Users\[username]\AppData\Roaming\Apple Computer\iTunes\iPad Software Updates
iPod touch
C:\Users\[username]\AppData\Roaming\Apple Computer\iTunes\iPod Software Updates
Note: To quickly access the AppData folder, click Start, type %appdata% in the search bar, and press the Return key.
Windows 8: Move the cursor to the upper right, click the magnifying glass, type %appdata%, and press the Return key.
make sure you clear the host file as umkvec  stated  ....