When I run any executable file, system goes to DOS MODE!!

I have really a very annoying problem. For about two weeks now, everytime i try to install new program, when i run the executable file, the system goes to DOS mode and return the usually message "Program too big to fit into memory ". I reinstalled windows (Win XP) buit it didnt solve the problem. I have tried many programs with no success. PLEASE HELP ME! Some of the programs i have tried include; wpsetup.exe, sdtrial.exe, fifa2005.exe. NOTHINGS WORKS!

 

Download - unzip - run the following Doug Knox EXE Files Association Fix.

 

plz help

I did what u said, i didnt solved the problem.
i get a feeling it a kind of DOS hijack, if that kind of hijacj exists, rally in deep darkness.
plz help

 

That's from another thread that describes a problem that may be relevant to yours. Also check that some other needed service may be inadvertantly disabled.

Reference for Default Services Settings.

If no joy, try running SFC /SCANNOW and have your install disk or source files available for possible need.