The alert was launched a few hours ago: apparently, the new version of Google Authenticator for the iPhone can cause a lot of trouble to Bitcoiners. Users all across the web are warning other cryptocurrency owners to not upgrade their version of the program or all their keys will be lost.
According to another member of the forum, “there are many people reporting it online”. ‘TsuyokuNaritai’ also said that Bitfunder has announced the problem on their webpage with the message “Error: Google has updated their authenticator app. Do not upgrade the app. Many users have reported that the upgrade has erased their stored codes needed to login. If you wish to update you will need to disable 2-factor on your account first so you can re-activate it after the app update”.
In the meantime, ‘picobit’ said on Bitcointalk.org that he had been able to recover from the problem. This was how he did it:
I recovered from this mistake. This should work on both jailbroken and unmodified iPhones, and will not loose your jailbreak if done correctly (point 5):
1) Swear at Google (OK, most of you have probably already done that)
2) Delete the Google Authenticator app from your Phone.
3) If iTunes sync automatically with your phone, you probably want to turn that off first. Also, if you sync over WiFi it may already be too late – I really do not know.
4) Connect your phone to iTunes. Enable the panel on the left. It shows “LIBRARY”, “STORE”, “SHARED” etc and also the name of the phone. On newer iTunes it is disabled by default, choose View / Show Sidebar.
5) Right-click on your iPhone, choose “Restore from Backup”. DO NOT use the normal restore button on the main window, as that will also restore the firmware and wipe and restore everythin (it will take ages resyncing, and any jailbreak will be gone).
6) After restoring, iTunes will resync your phone and reinstall Google Authenticator. If you did not sync or backup since upgrading the app, the old version INCLUDING KEYS will be back.
7) If jailbroken, install Update Hider and hide the update to GA (I have not done this yet myself, but it should work).