Helping people with computers... one answer at a time.

DLLs can go missing for several reasons from accidental deletion to corruption or more. We'll look at some of the common causes and steps to take.

I recently installed a firewall and downloaded the security updates from the Microsoft website. I am unable to open Outlook Express, even when offline. It says it cannot load one of the .dll files (though the file exists in a folder).

It depends on the program.

In this case ideally we'd get a little more information, but lets see how far we can get and come up with some general troubleshooting rules along the way.

"It cannot load the DLL" could mean several things and unfortunately we don't know what the exact error message was. If it couldn't find it, it's possible that the DLL is simply in the wrong place since the person asking pointed out that it was on the disk. If it had a problem loading it, then perhaps it's corrupt or perhaps it's in use by some other application.

For a missing, misplaced, or corrupt DLL, reinstalling or repairing the application is often the right course of action. It's possible that this is a Windows XP DLL, in which case a System File Check might repair the problem. If it's a Outlook Express DLL, then reinstalling Outlook Express (typically with the latest version) could be the right way to proceed.

If the DLL is in use by another program it's possible that program has locked access to it for some reason. The techniques in the previous article How can I find out who is using a "file in use"? can be used to determine who's using a DLL. Perhaps shutting down that program, if possible, will allow you to start Outlook Express.

And of course, it's quite possible that it's none of the above. Error messages typically contain important information to help track down these types of things, so we'd probably need to see the specifics to make a further determination.

Article C1966 - May 31, 2004 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

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June 4, 2004 9:52 PM

DearLeo, I always see you in techtv callforhelp for so many years.I used to read all your article in the wed( I am sorry to say we all miss you and we all can't get on only can get g4techtv.I would like to say the new g4techtv is way...way...out.can you please let us know how can we get the old techtv back we miss it very much.thank you fro all your malaysian viewer

June 4, 2004 9:55 PM

While I appreciate the comments ... I'm not that Leo. Please read:

I also miss TechTV, but for what it's worth, it's not coming back.

June 29, 2004 6:38 AM

What happen to call for help i cant find it anymore on Tv or in the web sites ?

June 29, 2004 9:06 AM

CFH was canceled when TechTV was purchased by G4 TV. Oh, and by the way, I'm not that Leo - read this article:


July 2, 2009 4:50 PM

The most common missing DLLs for Vista are the Direct3D support dlls. Like d3dx9_32.dll, d3dx9_30.dll, and d3drm.dll

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