can't connect GPS to ArcPad

[MichaelHeyroth]

I am getting the error "No datum transform found from D_WGS-1984 to D_unknown"
when trying to initilize the gps in Arcpad.
GPS is connecting fine with other programs.
what setting is wrong?  Any ideas?
More info
When I open a new map with no data/shapefiles it will connect just fine to the gps.  I then add shapefiles/layers and everything works perfect.
BUT,
after I close the map and go to open it again I get the same above error messsage.  When I try to make the GPS active, i get that same error message.
Arrrrrgh

[BrettBlack1]

From what you have stated above it sounds like you may not have loaded the HARN and NADCON tables from the ArcPad Deployment Manager onto your mobile device. If you reconnect your device, then install both of these under "Install Datum Transform/s for Windows Mobile" it may take care of your issue.

[jasonblocker1]

sounds like you are lacking a projection with your data