Driver File Omissions - Check It Out

[Brian R.]

This is a general information post for anyone who can use this information...

If one goes into the Device Manager (System Properties) and list the driver files associated with, for example, your video card, modem, sound card, NIC, etc., you will see every file Windows is using to operate that device. Most of the file listings are of the form:

C:\WINDOWS\SYSTEM\SERIAL.VXD

for example from my modem listing.

A potential problem exists when Windows cannot find a specific file it is looking for. When this happens, it puts the name of the absent file in parentheses after the name of the generic driver file it is using as a replacement. This looks like this:

C:\WINDOWS\SYSTEM\VMM32.VXD (vcomm.vxd)

In this case, vcomm.vxd is missing from the c:\windows\system directory.

The cure for this problem is to go to the correct cab file on the Windows installation disk and extract the vcomm.vxd file into the c:\windows\system directory and then reboot.

You will then find the correct file listing in the device manager.

You can find the identity of the cab file you need (for a specific driver file) by searching the Microsoft web site for the "file name" and "cab". I have found most of the files I need (Win98SE) are in Win98_53.cab or Win98_54.cab.

I have found, at least in my two Win98SE installations, that every display adapter, mouse, NIC, IDE controller, and modem is missing at least one file with VMM32.VXD substituted in each case.

FYI


[This message has been edited by Brian R. (edited 20 September 2000).]

[Nick L]

thanks, another windows secret revealed

[Wombat]

Ummm, actually, no.

If you look around a little more on the web, you'll find that vmm32.vxd is a mass driver, sort of a monolithic scheme. It has all the functionality of those little drivers built into it. And it's actually faster this way. If you're comfortable messing around with your system, you can even get vmm32.vxd to be rebuilt, if you fancy.

[Brian R.]

If it's faster or better in some way, why would Windows request other files? Why not just load vmm32.vxd all the time and not report missing files? I don't get it. To me smaller is better.

[Rags]

The reason win98 reports it is because this sometimes causes problems and necessitates puting the proper file in it's place. There is also a utility in win98 that you can do this with if you want to dig around hard enough

Rags

[Brian R.]

For a reasonable explanation see:
http://www.infinisource.com/techfiles/vmm32.html

[Kruzin]

Relocated to the General Hardware forum

[xortam]

From MHW version of this thread ...

Actually, the reason I brought it up is a guy at work recommended strongly that we replace all cited files to be used instead of vmm32.vxd. Since he knows more about Windows than I do, I pass his recommendation along

Well Brian, I guess you can go back to work and teach your "Windows expert" something.

[Brian R.]

No chance. I'm not convinced that replacing vmm32.vxd is a bad idea. I don't care how long it takes Windows to load (up to a point). There is something about using a complex file in place of a few fragments that I don't necessarily like.

Like Rags said above, it may cause problems sometimes, causing you to replace it with the other file. Why not just do it intially and put up with a 100-msec longer load time. It's only 5 or 6 files.

[This message has been edited by Brian R. (edited 21 September 2000).]

[Rags]

Actually, it takes up more memory space too, in addition to adding about 30 seconds on your boot time. That link is incorrect in saying that windows does not have a bug where the vmm file doesn't get installed complete with all the files that are necessary. MS, on their knowledge base website, has a pretty lengthy explanation of vmm32.vxd, and the problems that arise from it when upgrading from a previous windows install. Fresh installs rarely get this problem. What happens is when the upgrade is taking place, the setup engine looks for installed vxds that can be covered by vmm, and sometimes it a)finds the wrong one for your device (surprise, surprise); b) loads the wrong one (similar to a); c) the vmm version of the particular driver you are using doesn't work well with your device (most common); d) the vmm gets corrupted. I am sure there are more reasons for vmm to cause problems, but most failed upgrades I have seen is caused from the vmm causing shit cascades.

Rags



[This message has been edited by Rags (edited 21 September 2000).]

[Wombat]

Agreed. If you need to rebuild your vmm32.vxd, there's ways to do it.

Brian:
>There is something about using a complex file in place of a few fragments that I don't necessarily like.

Umm, that's one of the big things that MS has done to NT to make it run better. Originally, NT was a true micro-kernel. However, this proved too slow. NT4 now has video, and some networking functions, built into the main core. So now the most intensive NT functions are monolithic (one, complex file), and the lesser functions are abstracted out MK style.

[Brian R.]

Rags - Which configuration takes up more memory space? The use of vmm32.vxd or the individual files?

30 seconds? Nothing I've done has added 30 seconds to my boot time. Under what conditions does this much additional time get added?

Wombat - I think this type of approach is moving toward the more complex. I like things better when they're simpler, rather than more complex. A little slower is good if it causes less trouble. In the same vein, I oc my processor only to the point it still functions without detectable error.

[This message has been edited by Brian R. (edited 21 September 2000).]

[Brian R.]

Well according to Rags and at least one other, they don't always work as advertised.

Also, when you have 256 MB of RAM and 20 GB of HD space, who cares if the individual driver files take up some space. Reliability is more important than space.

Also, the fast that they LOAD slower is the issue and not run slower. I understand they end up with the same functionality in the end after the vmm32.vxd file has been loaded.

Give me a break Gurm. You are not the final word here.

Not the end of story.


[This message has been edited by Brian R. (edited 21 September 2000).]

[Rags]

Monolithic is faster. Takes a smaller memory footprint, faster to boot, and is just simply faster when the kernel is designed to take advantage of it. Yes, there are problems with it, but most of the time it's because you are upgrading from a previous windows install such as win95 or win 3.1, I am not going to get into a lot of detail, but this is one of the main reasons I suggest doing a clean install of OS's instead of upgrading (unless you are willing to needle through the problems, as I do).

Rags

[Brian R.]

Rags, are these differences significant, or just measurable? If the memory used is an additional 1 MB out of 256 for example, I don't care. If it is 1% slower, I don't care either. It still sounds like there is an additional reliability factor involved.

The reference I gave above does not agree with you about the functionality. He believes (and quotes MS) that there is only a difference in loading time.

[This message has been edited by Brian R. (edited 21 September 2000).]