Help. Samsung s300

Archived from groups: alt.cellular.gsm (More info?)

Can anyone help me. I was given a Samsung SGH-S300 which was locked on
Orange. I had the restriction removed so it should be ok to use a different
network other than Orange. Well, this is where my problem is. I have a
Virgin pay as you go sim which registers with the network when I switch on
the phone, but can not send or receive phone calls. My Virgin sim works in
other phones and my O2 contract sim works in the Samsung. Has the unlocking
been unsuccessful or is there an incompatability problem with Virgin sims
and this phone.

Any advice would be great.

Cheers