(Null) not a valid win32 application

[Unnat]

I had installed Windows Xp along with Microsoft Office 2003 on my pc. The problem is that when i try to whenever i try to open Microsoft Word it gives out an error message stating that "null is not a valid win32 application". But some of the programs of MS-excel seems to be working on my system. So, can any body tell me that what i need to do in order to get rid of the above issue? Does any body knows about it? Kindly provide me the correct solution for the above issue.

[Macarenas]

I think you need to go in to your Microsoft Office and then try to go in to Repair option and try to repair it. Might be that some of your files may have been corrupted and that may be the reason which might cause your the above problem on your system.

[ThoMas321]

Check out whether you system is been not affected from any kid of viruses. Try to scan your system with some good recommended antivirus program. It might help you to get rid of viruses if your system may be affected from it.

[chroma]

I think you need to uninstall your Microsoft Office from your system then you need to reboot your system in order to reset your settings, then try to re-install Microsoft office on your system and then reboot it in order to check out whether it works properly or not on your system.