Fix “SIM card unavailable” in Sony errikson X10 xperia
The problem here is simple… The phone is look ing for a number on the sim. This is a special field which the phone expects to find. When it is not there it throws up an error. It appears that only sony phones use this field for any purpose and for reasons only known only to Sony you cannot edit this field with a 400 pound smart phone. The quick fix is to put the sim in an older phone and try to update the field. You are look ing for some reference to “your number” or “special number”. However it appears that only some phones will do the trick. People have reported success with other Sony phones and I can confirm that a Blackberry will do it. Goto settings>sim>advanced and you will see the blank number field. Fill this with your own number and save it. Put sim back into xperia and you should have got rid of the error. Sorted.