RX3700 - XXX.exe is not a valid Pocket PC Application

Hi
I am having problems with my HP RX3700 when trying to start exe files.
The message that appears on the screen is this
"XXX.exe is not a valid Pocket PC application" .
I tried to solve it according guidlines from this link
http://windowsmobilepro.blogspot.c [...] et-pc.html
but it was unsuccesfully .
From Hp support center the answer was : " the only one that we can offer u is to flash your device with latest rom file" - the ROM file which is uploaded on their support server fixes just some little problems with ie and that's all . it was not what i am looking for and didn't solve the problems .

I'll be very grateful if someone helps me .

Info for my device :
model : HP RX3700
OS : Windows Mobile 2003 SE ver 4.21

Hi Even i Have also going through the same problem ...I Have the HTC Kaiser phone but when i start the .exe file. the same message apperars.
"xxxx.exe is not a vaild pocket PC application"

hey i have made my application on the windows Mobile 6 profesional SDk(ARMV4I).
also when i got the problem in building my application "fatal error CVT1109: target machine "THUMB" requires "/WINDOWSCE" .....i just go to properties of my project and change the linker->system->subsystem-> in to WindowsCE (/SUBSYSTEM:WINDOWSCE)..........

is because of this problem my applicatuion is not working?
I 'll be gratefull if someone help me.

Thanks