Lost half of my contact one day and some of the contacts that still remaind has their data corrupted: phone numbers gone and e mail addresses turned into 2 digit numbers, did it happen to anyone, whats the solution?

Question

Half of Contacts are lost, some of those remaining have their numbers gone and e mail addresses corrupted. what should I do? (after I tried to restore the data it happened again)

Answer 1

Can't edit my message anymore, so for the tldr crowd (too long didn't read), here is a shorter version:
The good:
E4200 worked fine for about 15 hours with great throughput and link quality (with one brief disconnect in the middle - online gaming software shows brief disconnects that otherwise go totally unnoticed).
The bad:
Wireless on the E4200 stopped broadcasting entirely (to a Windows 7 laptop with a 802.11n 2.4 GHZ USB adapter).
I had switched between two adapters that use the same chipset, same driver and in fact show up as a single device in device manager) without rebooting the router but it worked (fine) for an hour after I swapped the adapters.
Right before I rebooted it, I checked and the E4200 was not hot to the touch and wired internet was still working after the wireless radio stopped working.
A reboot of the router cured it.
The open question as to the root cause:
Now I want to know whether this wireless radio ceasing to broadcast (requires a reboot of the E4200) will happen daily?
I.e. I want to know whether it it really is overheating (then again why would only some have that problem needing to reboot daily while others have gone weeks with the E4200 without a single reboot being needed and without any problems occurring) or whether it had to do with changing the adapters back and forth without rebooting the router. Keep in mind that the router worked fine for an hour or so after I stopped swapping the adapters.
Extra question:
Will getting a Cisco AE1000 USB adapter perhaps help? (I know this is a loaded question and their is no easy / sure answer, but even a "maybe" or reasons why it might help at this point would be better than nothing.
Any similar experiences (with the router needing to be rebooted to get wireless radio back on) would be appreciated as it may help myself and others experiencing these types of issues.