I know there is a way to specify that any items in the combobox should not be removed during binding. I did this in an asp.net app not long ago but I dont have access to the code at the moment... Basicly you add the empty string to the combo set the (at the moment unknown) property not to clear the combo and then you do the databinding. Workaround: Do the databinding and then: CBPersonnel.Items.Insert(0,"") BR Fredrik

And that't when it gets messy! In order to swith on/off the led on the hardware you must send the correct data on your serial port. I have written some protocols before for serial comunication and they all start with a command sequence. In your case I would have had a command LED_CONTROL which would have been the character "L" and then which state to put the led in "0" or "1". By sending "L" on the serial port the hardware knows that next character recieved will contain "0" or "1" and when I send "0" the hardware swithces the led off. Two weeks ago I wrote a program to print stickers with a Intermec PC4 printer. http://www.intermec.com/eprise/main/GSS/Service/Content/Manuals/Show_ManualSearchResults?Product=PRTRPC4&Language=English[^] Take look at the Programmer's Reference Manual. That's why you must know the protocol for the hardware communication. BR Fredrik

Interesting... Can you email me the code or post it here and I'll take a look at it?

In btnAddColumn_Click() you assign fldName and fldAttribute and add them to the ListView but in btnCreateTable_Click() you don't iterate the ListView to retrieve all added columnnames and datatypes. You only use the las assigen values for fldName and fldAttribute. BR Fredrik -- modified at 10:05 Wednesday 12th July, 2006

When you say "bind the second table to second combobox and the third table to the third combobox"... Are using three different DataAdapters and three different DataSets?

Are you running the DB, webservice and client app on the same pc? Have you tried using OracleClient instead om ODBC? BR Fredrik

Then you must know how the hardware reads the data. Meaning you must know the communication protocol. What type of hardware is it? BR Fredrik