Tonight I decided to dust off my old Lexmark 6170 printer/scanner and attach it to my Windows 7 64bit machine. Well, I was expecting it but was hoping for some miracle that it would not happen. The installation of drivers failed. Windows's automatic update could not find any device drivers that would work. I tried to download driver from some well known driver sites. That did not help. Finally I went to Lexmark's support site (I should have done it the first place anyways). After searching around I found that Lexmark does not have drivers for Windows 7 but they have remark on their page to install their Windows Vista drivers and it should work. And I did exactly as they asked, and it did actually work.

Here is the URL from Lexmark support site from where you can download the package. Here is what you need to do.

• Goto Lexmark X6170 Suport page.
• Near end of page, it has option to pick operating system. Select Vista 64 if you are installing on Windows 7 x64 otherwise pick Windows Vista x32.
• It will present you with a link. This link has lot of text. Trust me it is a link that will take you to download.
• Rest is standard. After clicking on the link you will get your download package. Run it to install the drivers for Lexmark 6100 series on your Windows 7 machine.

After I installed Windows 7 x64 device driver on my Windows 2008 Server x64 laptop, I looked my wireless network connection utility and noticed that my wireless connection was not working. I looked in device manager and saw that there was no problem with driver installation. There was no yellow mark against the wireless card device. Then I went into Manage Network Connections windows. The icon was there for wireless connection but it was in Disabled. I tried to enable it and it won't enable. It kept getting back into Disabled and every time I tried to enabled a windows error message will pop up asking to check for solution online. I decided to look in the event log and found there were plenty of errors with following message.

One thing was clear that network utility was trying to do some action and it was failing in WLanApi.dll. This dll has implementation of Wireless Network APIs. Then it clicked that on Windows 2008 Server, Wireless LAN Service feature is not installed by default. So simple solution is to goto Server Configuration wizard to launch features window and add Wireless LAN Service feature and finish the installation and wireless card will work fine.

This issue has been bugging me for months. Everytime I close lid of my monitor and later on open it to resume work from where I left, its a 90% chance that my laptop will be throwing BSOD and smiling at me and saying, how dare you leave device driver programming, i will remind you how much you liked blue color. A normal restore after hibernation is just a luck. If you actually get a normal store, I will say go play lottery because that will be your lucky day. Anyways, this has been an ongoing problem that laptop will throw BSOD after coming out of hibernation. I have looked around on all search engines. And it seems that a lot of dell laptops have been having this issue. This is caused by a threading issue in device driver. Finally I decided to look at the minidump generated by this BSOD to see whats going on. See what I get when I run !analyze -v command in WndBg debugging tool.

kd> !analyze -v
*******************************************************************************
*                                                                             *
*                        Bugcheck Analysis                                    *
*                                                                             *
*******************************************************************************

THREAD_STUCK_IN_DEVICE_DRIVER_M (100000ea)
The device driver is spinning in an infinite loop, most likely waiting for
hardware to become idle. This usually indicates problem with the hardware
itself or with the device driver programming the hardware incorrectly.
If the kernel debugger is connected and running when watchdog detects a
timeout condition then DbgBreakPoint() will be called instead of KeBugCheckEx()
and detailed message including bugcheck arguments will be printed to the
debugger. This way we can identify an offending thread, set breakpoints in it,
and hit go to return to the spinning code to debug it further. Because
KeBugCheckEx() is not called the .bugcheck directive will not return bugcheck
information in this case. The arguments are already printed out to the kernel
debugger. You can also retrieve them from a global variable via
"dd watchdog!g_WdBugCheckData l5" (use dq on NT64).
On MP machines it is possible to hit a timeout when the spinning thread is
interrupted by hardware interrupt and ISR or DPC routine is running at the time
of the bugcheck (this is because the timeout's work item can be delivered and
handled on the second CPU and the same time). If this is the case you will have
to look deeper at the offending thread's stack (e.g. using dds) to determine
spinning code which caused the timeout to occur.
Arguments:
Arg1: 8a3bbae0, Pointer to a stuck thread object.  Do .thread then kb on it to find
	the hung location.
Arg2: 8a63db50, Pointer to a DEFERRED_WATCHDOG object.
Arg3: f78c2cb4, Pointer to offending driver name.
Arg4: 00000001, Number of times "intercepted" bugcheck 0xEA was hit (see notes).

From this description, somethings came to my mind that could be potential reason for BSOD. I remember that my problems started when I upgraded my laptop from 1G to 2G RAM usage. Well that means that size of hiberfil.sys increased as well. That translates to another ripple effect that underlying drivers that have to process saved state have to perform more work as well. What may be happening is that the video drivers do not want to be stuck in long loops and they end up doing a BUGCHECK.

Well the obvious solution at this point seems is that you need a newer driver. Well, not it depends on your video card vendor. For lot of older systems, they don't have new driver that can deal with this issue. And they do not want to spend resources on fixing this in old drivers to release a fix. They want you to upgrade to new video cards. And for laptop vendors, it translates to that they want you to buy a new laptop from them. Hmmm.. make the consumer buy a new laptop or offer a free upgrade to new driver. Well, you know the answer.

Here are few things that I tried to see if this problem goes away.

• Did memory diagnostics using Memtest tool from MemTest.Org. It took me about 3hrs to run diagnostics. All tests passed. So my memory is OK.
• Somebody suggested, how about reinstall of OS. For kicks I did that as well. That did not help either.
• Then dell support suggested, you need to install all our tools and drivers in certain order. Well i did that as well. That did not help either.
• How about shutting down machine and not try to hibernate. Tries that as well but of no use.

After looking at dump analysis, here is what I think is worth trying.

• Removing couple of DIMMs to see if this problem goes away. No i am not suggesting that you need to run your laptop at lower memory. I am just saying how about seeing if increased memory is the real problem that is putting video drivers in tail spin.
• May be trying with a different brancd of memory and see if some corruption in DIMM may be causing slow processing of hibernated state.

If you do find a solution to the problem or updated drivers, please post a comment here. There are a lot of users who will benefit from it.

Last night I installed a new video card in my machine to try some new DirectX features. Well, the worst that could happen, did happen to my machine. It refused to restart after device drivers were installed. I tired everything I could but it will not move. Machine will not go into safe mode either so I could install device drivers. Finally I had to take brute force approach. Since there is always a default device driver present on board as well as in windows, trick is to get rid of the new driver. To accomplish this, following things you will need to know.

• What is name of the driver files that got installed? That is not hard to find from manufacturer's site. Or you can use another machine and pop-up in CD and look at the files contained in the CD using windows explorer.
• And you will need access to another machine.

Here are steps you can try

• Remove your hard drive from bad machine.
• Goto another machine. Take out its hard drive and change jumper settings to make it master hard drive. You will find the settings instructions right on the drive itself.
• Change jumper settings on drive from bad machine to make it slave and put this drive into second machine.
• Start your second machine.
• You should be able to see hard drive from bad machine in windows explorer.
• Goto Windows > System32 > Drivers folder and delete the device driver files for new video card or for that matter for any device that may cause your machine not to boot. Be very careful on this step. Make sure that you are deleting these files from slave drive which you inserted in good machine from bad machine. Otherwise you may accidentally delete drivers from your good machine's operating system.
• Take this drive put now. Also take out drive of good machine as well and reset its jumpers to make it stand alone hard drive (assuming you only have one drive in your machine). And reset jumpers on hard drive of bad machine to make it stand alone as well.
• Put the drive in your bad machine and fire it up. Hopefully it will boot and you will be able to interact it with standard 800x600 resolution default display driver.
• Get a new video card or device driver for your new video card and install it.

Hopefully these steps will help you resolve your bad device driver issues as well.