The Nokia 5190, 6190 and 1100 (non-ENS) has a memory issue that prevents it from using any SIM card newer/larger than the older 32K SIM cards. When Cingular/New ATT came out with the 64K SIM they sent notices to previous and current users of those phones of the problem if they upgrade/replace their old 16K and or 32K SIM cards to the newer 64K SIM, their phones would not work as they would freeze up and or reboot over and over again. Most current AT&T (Cingular/New ATT) customers have either the National, 3G/UMTS or 3G/4G SIM cards which are 64K based.
I was able to unlock my Pacific Bell Wireless Nokia 5190 a long time ago using one of those DCT3 calculator codes. I was able to use my (still at the time working) AT&T Wireless SIM and my T-Mobile SIM. When I tried using my 64K National SIM from the new Cingular/new ATT, it froze and rebooted over and over.
No sense in trying to pay some site for an unlock code if your SIM from AT&T is current (i.e. activated after 2006).
Not sure if T-Mobile secretly moved on to the newer 64K based SIM cards as I last had them back in 2008 and the SIM I had was activated back in 2003.
Better off looking for an unlocked Nokia 3590/3595 or 6010 for cheap instead of trying to unlock and re-use the 5190. At least those older phones were able to use the newer SIM cards.
As for selling it, not even worth posting it unless you want to sell it as a cool alarm clock.
If you feel that you have to correct some of my posts for my capitalization of some of my words, then just bear with it. It's just a discussion forum where some may be limited by time to answer in well-versed and eloquent sentences.
I already got a PHD (Plain High School Diploma) so ignore my style of writing and I'll ignore your ignorance.
Subject: You can read this-trust me!
I cdnuolt blveiee taht I cluod aulaclty uesdnatnrd waht I was rdgnieg. The phaonmneal pweor of the hmuan mnid. Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoatnt tihng is taht the frist and lsat ltteer be in the rghit pclae. The rset can be a taotl mses and you can sitll raed it wouthit a porbelm.
Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe. Amzanig huh? yaeh and I awlyas thought slpeling was ipmorantt!
When asked if I see the glass half empty or half full, I responded I see just a glass of water.
Now you know how I think.