I just purchased a ppc4100 from Ebay that was supposedly unlocked. I have the dll unlock file, called rilgdsm, and still cannot unlock my phone. I have followed all of the instructions and my phone is still saying At&t and refuses to recognize my very functional tmobile sidekick sim card. I don't know what 2 do. the ebay seller send me a ringdsl file with instructions. this file did not work. I also downloaded a file from this forum, that appeared to be the same, and it could not override the previous file because it said that the file was in use. I have been unsuccessful in making multiple attempts because it always tells me that the rilgdsm file is being used (something like that). What am I doing wrong? please advice!

hard reset your PPC and try again.

where I get confused on the instructions to unlock PPC is all the files always say to copy the rigdslm file and then power off the ppc. then it always instructs you to soft reset and then it should reboot. when my ppc is off and I attempt to reset, it does not reboot. I can only get it to reboot if I turn the device back on and then reset.

after hard resetting ,use the new name to synchronize with your computer then copy the .dll file to your ppc. it's not like the instructions describe,u should soft reset your ppc mannal.sometimes it take a long time to reboot,just wait or soft reset again.

I just received a new phone and same result. So it is not the phone and it is defintely not my sim card. Do I have to adjust any settings?

I am having the EXACT same problem. Have done everything I know to do. I will keep my eyes on this thread.