Archive for Windows

Windows Server Says, “Network Cable Unplugged” When It’s Not?!?

Once again, stuck managing a Windows box. Yeah, I know, I’ll whine, bitch, moan, and cry you a river another time.

The Problem: Using the secondary NIC (PNET/VLAN), I found a lock of packet collision during negotiation, handshaking, and identification, causing Windows to give up and basically say, “well, since it’s not working, the cable must physically have been removed, because there’s no way I could ever be wrong.”

Wro…. err…. incorrect, Windows. (You’re wrong.)

The Discoveries: The truth was, at least in my case, that it wasn’t properly handling the gigabit capabilities of the card on the box. I’m not the administrator for these machines (though they’re housed in our datacenter), so I can’t be certain that nothing had changed recently, but their staff said nothing at all had been modified. Perhaps that really was the case, and nothing had been changed — Windows has been known to do stranger things than this, of course, sometimes out of the blue.

The Solution (for my case): Go to the screen where you can view your network adapters (your version of Windows dictates the path of navigation, hence the ambiguity). Next, right-click the adapter with the “Network Cable Unplugged” message and click “Properties.” Click the appropriate button to configure the network adapter. Then click the tab on that dialog for “Settings” or something of the like (sorry, but I logged out in a hurry, so this is from memory), and you’ll see a list of parameters on the left, with their values on the right. Find one related to speed and duplex, and if you see it set to “Auto” or similar, drop it to “100Mbps Full Duplex” and click OK. Close the properties dialog by clicking “OK” and see if the settings are already bringing the network adapter back online. If not, disable and re-enable the adapter, and – if it was indeed the same issue – you should be back online within a few seconds.

Windows 7 DWM (dwm.exe) High CPU Performance Issues

On this system, I’m blessed with a triple-headed setup: I have three nice LCD monitors on my desktop which create a panoramic view of my terminal screens. I’m also cursed with Windows 7 and it’s [many] flaws. Lately, I’ve been having an issue with Windows 7’s Desktop Window Manager (DWM, shown as dwm.exe in Task Manager) consuming large amounts of CPU and RAM resources. After a bit of snooping around, I found a simple fix:

1.) Click the START button.
2.) Type “powershell” into the “Search programs and files” box.
2a.) If you see a menu item for PowerShell, open it.
2b.) If you do not see a menu item for PowerShell, this won’t work for you.
3.) Type “net stop uxsms”
3a.) Try this if you want a stripped-down version of your ALT+TAB and fewer bits of eye candy. It’s just like WinXP, and runs quicker. If your ALT+TAB was slow, it should now zip along quite nicely.
3b.) If you want your effects and nicer ALT+TAB screens back, type “net start uxsms” and you should be good to go.

Debunking The Vista-ry: Case of the Disappearing DNS

Yeah, I’ll be the first to coin the term Vistary. I’ll use it to reflect the many, many issues Vista still has that crop up at seemingly random intervals with no warning or explanation.

Lately, the most enjoyable problem has been intermittent DNS failure requiring a full restart. At seemingly random intervals, I’d be happily plugging away at whatever it was that I was doing, only to have Vista take a crap and refuse to do any more named translations. Here’s a real-world scenario from this morning:

While chatting with Eric Butera on IRC and simultaneously bopping around the web on Chrome, BAM! Once again, the DNS drops out. Aside from my vast, genius-level knowledge of every single aspect of the world around me, how did I know it was just DNS? Elementary, my dear Watson: as in all of the other occurrences, IP-based connections continue to operate normally, while all name-based connections (including connections to MSN’s Messenger service, Gmail, etc.) all start to fail and die off.

For the life of me, I couldn’t figure out what the issue was, nor how to recreate it to debug it. Searching Google did little more than to reveal others who had the same issue, with some suggestions as to what may be the cause and solution (all of which were later denied to solve the problem). My router was fine, UPnP wasn’t an issue, and the parity-error-checking device between the chair and the keyboard was operating at relatively sane levels at the moment.

After getting to the point where this system was about to join its ancestors in the grave, I found my own solution.

Even though I’m using WiFi, which – on here – has no option to share the connection, it was causing an error for some reason. Perhaps something in the networking section of the Windows kernel causes its internal (and proprietary closed-source) BIND-like implementation of a DNS client to die.

Restarting the network interface has no effect.

“Repairing” the network connection has no effect.

The only way to get DNS to Just Work™ again is to reboot the machine…. so it seems.

However, I found that – even though I had my ethernet interface disabled – Internet Connection Sharing (ICS) was still causing the interruption there. So here’s what I did:

Go to Start -> Control Panel [-> Classic View] -> Network and Sharing Center -> Manage Network Connections.

Right-click on any interfaces listed as being “Shared” (even if they’re disabled) and click Properties.

Click on the “Sharing” tab if it’s available. (If not, move on to the next interface in your list and repeat the steps above. If this was your only interface, stop reading…. this won’t work for you, sorry.)

Uncheck the boxes on that panel and click OK.

If you enabled the interface above, don’t forget to disable it again (if you want).

Voila! It’s a hotfix, so if your system was acting up due to a problem with ICS as well, then you don’t have to restart or anything, your DNS lookups will go back to their Just Works™ status. If it’s not immediately back to working, make sure you didn’t disable the interface you were using to access the Internet.

“Logon Process Has Failed To Create The Security Options Dialog” Error

Despite my preference for non-Windows operating systems, I do keep some Windows versions and at least one Windows machine in my arsenal. Here in my home office I have a desktop running Mandriva (I’ll get into that at another time) with a laptop next to it running Vista. I know, I know…. “bad Dan.” Save it. I already know.

Anyway, in the last week or ten days, Vista locked up on me. It would slug itself along as if a process was using up 100% of the available CPU and memory. It’s not a top-shelf machine, it’s just a Dell Inspiron 6400 w/ Core2Duo CPU and 2GB RAM – my wife, Debs, and I have similar systems.

Vista would hang, nearly unresponsive, and 15 minutes or so after I hit CTRL+ALT+DEL (nearly immediately, due to my severe lack of patience with personal computers), I finally had a response, though still no task manager. Less helpful than most BSOD‘s, the dialog stated simply:

Logon process has failed to create the security options dialog
Failure – Security options

Neat.

After poking around the Windows internals as best I could, while still being a good boy and not violating any possible terms of my license (yes, it’s a Genuine copy), I confirmed my suspicions: Vista still sucks.

However, after working around a few things, it was actually Microsoft’s “Safe” Mode (sic) bootup that helped me out. By trimming down the processes, I was able to debug the issue and narrowed-down the culprit: AcroRd32Info.exe. In fact, the whole Adobe Acrobat Reader installation was crapped-up. It turned out, every time I would load a multilayer PDF, it was causing a serious buffer overflow issue that was spiking CPU usage as high as 100%, memory usage to 99.6% of available RAM (spilling over into virtual memory) and maintain those levels until I hard-booted the machine. All total, between the three screwups, I lost about 3.5 full weeks of research for an AI neural network application I’ve been building, but nothing permanent. It’ll be like a drunken bender to the brain. It will survive.

Anyway, the lock-ups were primarily my fault, as should be expected. I was using an outdated version; I was using 8.1, whereas 9.x is the current version as of this writing. I installed the latest version and tried to reproduce the overflows — nothing. Keeping my fingers crossed, I think I can mark this as solved.