I have a Merlin XU870 3G datacard and up until today it has been working fine.  When I went to use it today I received an error message saying SIM not ready.  I took the card out and replaced it but still the same error.  I took the SIM out and put it in my old datacard (Merlin U630) and it worked fine so it appears it is not a SIM problem.  I am running XP.  When I go to Control panel, phone and modems the card shows up in COM9 and when I go into properties and diagnostics it detects the card and responds.  I have downloaded and reinstalled the VMC software.  If I go to diagnostics in the VCM software my modem dows not show up under "GSM".  The blue light flashes on the card when it is inserted.  Can anyone help me with this problem.  Thank you