I have written an embeded program for switching the UART1 to data mode from AT mode.Now it has gone to data mode and I cannot use the port for at commands,not even I can download any program using AT+WDWL. So please kindly help me to fix the problem to bring back the UART1 port to AT mode.
Isn’t hindsight is a wonderful thing?! 
In my application, I ensure that there is a delay after the module starts before it switches the UART to Data mode - specifically so that I can type an AT+WOPEN=0 to stop the application, if necessary! 8)
If you’re very quick, you might find that it’s possible to get an AT+WOPEN=0 in before the UART goes to Data mode - do you have an application that can set this up as a single-key command?
Failing that, you’ll have to use the Wavecom DWLWin utility to re-flash the module - contact your distributor for details…
THANX again buddy.Please can u send me the winDWL utility and the required firmwire files along with instruction manual.I am using wismo quick q2406b module.
As awneil says, you need to contact your distributor for the tool…
Best Regards,
Jan
Is there any other way to stop the embeded application or to overwrite the embeded application?
Did you try my suggestion of getting the AT+WOPEN=0 command in very quickly as soon as the module powers-up?
Use Terminal Emulator, so you can paste command with then send command quickly.
i would suggest Jan’s terminal ! Because with Terminal Emulator, you need to synchronize the comm every time the module reboots (or every time you start the module)…
see : wavecom.com/modules/movie/sc … .php?t=995
ps : by the way, thank you Jan ! It helps me a lot in such cases… and in others too… 
I have made a VB program which can send AT+WOPEN=0 just by a button click.After making the module on I am sending AT+WOPEN=0 with a carriage return by clicking that button,but nothing is happening.Is the port permanently configured for data mode?Please suggest to fix the problem.