When connecting to a serial port there are a couple of things that could be causing the issue. The biggest problems are usually one of these:
- The app does not accept serial data.
- The RS-232 settings of the scanner and serial application do not match.
- The cable issue.
- The data is not using the termination character the application needs.
Are you using a Symbol 25-32465-20 or CBA-R01-S07PAR cable?
If so, do you know for sure your application accepts serial data? The scanner puts the data on the COM port and the application takes it from there. A good test is to try the scanner in Hyper Terminal if you have it. It is usually listed under: Programs>Accessories>Communications.
The M2004 series scanners default to 9600 baud (or bits per second), 8 data bits, 1 stop bit, no parity and no hardware or software flow control.
When starting HyperTerminal you may have to go through a screen that asks for a phone number. Just enter something and click OK to get to the next screen (sorry I can not remember exactly what that screen looks like- once it is set you do not see it again.) Next will be the Connection Description window. You will name the session (name it anything you would like) then click OK. Next is the Connect To box. Select your COM port in the Connect Using box, the first three boxes do not matter. When you click OK a Properties window will open. Most likely you will only have to change the Bits per second to 9600 and the Flow control to None. When you click OK your session should be active. You will have a blinking cursor in the upper left corner and in the bottom left portion of the window you should see the session time counting up. You can now try to scan a barcode. If the data shows up you know the scanner and cable are both working.
If you know your application accepts serial data (Word, Notepad, Excel do not) then it may be the application needs to see a carriage return at the end of the data. The CR is added by scanning Scan Options, Data Suffix, Enter from the M2000 Series Product Reference Guide. Test the scanner. If you still do not get data scan Scan Suffix, 1,0,1,3. Again all of these barcodes are in the M2000 PRG which can be obtained here:
Hopefully this information will be helpful in getting the M2004 working.