Hi Dennis,

OK, I have looked for the modem's manual and found out that the AT# (AT#CLS, AT#VSM, AT#VLS.. ) commands are nowhere to be found in its AT Commands Chapter. I saw them on a web site though.

A comprehensive manual is mandatory if you are going to work with a modem at this level. Try a search like this and pick your poison.

I have also tested these particular commands in a simple form made up of a txtString, cmdSendRequest and MSCOMM control.

cmdSendRequest merely does an OUTPUT of the ALLTRIM( .txtString.Value ) followed by a CHR(13) and waits for 3 secs and collects all Input values and shows it through a MESSAGEBOX.

I tried ATZ, ATI2, ATI3, ATI4 (ATI4 gave as a return value "Generic SoftK56 Data,Fax,Voice,Speakerphone PCI Modem") commands and they always return OK.

The best indicator of your modem capabilites is probably the response to "ATI7" command. If this errors, you definitely have the wrong modem :>)

Sending the AT#s however always returned an ERROR string.

Could it be that the modem we have does not support those types of commands?

Note that most of those commands I showed you are dependant upon the modem being in "Voice" mode, IOW following the "AT#CLS=8" command. Try these command sequences in a terminal emulator of your choice (Hyperterminal, Procomm, etc.) so you are sure of the complete modem response.