Re: PNLM list overwritten

I've seen similar behavior before -- particularly trying to write EF.PLMNSEL, EF.FPLMN, and EF.{O,H,}PLMNwACT on some US-carrier SIMs. This seems to be worse in the ones from AT&T MVNOs (I've tried ones from Red Pocket and H2O). Generally, the write just fails; but I believe I've observed some EFs get reset after a successful write/read. Are you getting a valid response from the UPDATE BINARY command?

Unfortunately, I haven't found a reasonable workaround for this. One ugly hack that seemed to work with some SIMs on an HTC One V (a recent Android phone ), is "priming" the SIM by first registering to the network using a old Nokia 3310 or similar; the connected data is stored on the SIM (EF.LOCI, I imagine? I actually never figured out why this worked.) and is good for a one-time use in the smartphone. Writable or custom SIMs are reasonably inexpensive, so for anything over a handful of devices in a test network (with manual network selection), that's probably the way to go..

Are you operating as MCC=001 MNC=01 (test network)?

(Apologies to the list if this is the wrong venue for this.) On Fri, Sep 7, 2012 at 8:15 AM, Dario Lombardo <dario.lombardo.ml(a)gmail.com> wrote: > Hil list > Today I've observed a strange behaviour when modifying the PNLM of > some real networks expired sims (to be used with osmocom and openbts). > I've put 001 01 on the top of the list. I've ejected and reinsterted > the sim in the reader many times, and I'm sure that the value has been > wrtitten. > When trying to connect to my test operator I get the message "your sim > card doesn't allow the connection to this network operator" from my > android phone. > Reading again the pnlm I see that the original list has been restored. > This astonishes me... Is is possible that the SIM overwrites the list > by itselt? Or is it the phone that does it? The android has an > original, not branded, operating system. > Thanks everybody for your help. > Dario >