An interesting issue I came across recently. Pressing CTRL + ALT + DELETE after switching on a Windows 7 laptop leads to a blank screen and no prompt for credentials. I have, so far, only seen this issue on laptops. The cause seems to be a module for Cisco’s VPN software called SBL. This issue is generally created when a user is connected to VPN and then closes the lid on their laptop, putting the laptop to sleep. Waking the laptop leads to a blank screen and rebooting the laptop does not help. You just get a blank screen after pressing CTRL + ALT + DELETE and eventually the prompt for CTRL + ALT + DELETE returns.
The solution is to uninstall the SBL module. You can do this by
1. Going into SAFE MODE (press F8 repeatedly after turning on the machine until you are promptedwith SAFE MODE options.)
2. Adding a registry entry to start the MSI installer service… REG ADD “HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot\Minimal\MSIServer” /VE /T REG_SZ /F /D “Service”
3. Start MSI installer service… net start msiserver
4. Uninstall the SBL module from Add/Remove programs
After a reboot you should be able to log in to Windows
It’s one of the most asked questions about Windows 7 and the answer is simple, absolutely not! There are few directories in the Windows 7 system root directory that you can delete without repercussion. All of the components in the operating system are found in the WinSxS folder. The WinSxS folder is the only location that the component is found on the system, all other instances of the files that you see on the system are “projected” by hard linking from the component store. An example of hard linking would be having a file called File1.exe (size 10MBs) located in C:\Windows\WinSxS. You can use a command in Windows 7 called mklink to create a hard link of File1.exe in say C:\Files. So when you look in C:\Files you will see File1.exe at a size of 10MBs but this is an “illusion” 😛 What you are seeing is a link to the file in C:\Windows\WinSxS. So File1.exe is not taking up 20MBs of disk space by being in two places, it is actually still only taking up 10MBs. So, although you may see files in various folders on your computer taking up diskspace they are really located just once in the WinSxS folder.
That explains why the folder starts off big, but not why it gets larger over time – the answer pretty simple. When a component is updated then new version is “projected” or hardlinked onto the system but the old version of the component is kept. So the more a component gets updated, the more previous versions there are of that component.
So to finish. Do not mess with the WinSxS folder
Update: After installing Windows 7 SP1 it is possible to reclaim a few GB’s of space by making SP1 permanent and removing older files and SP1 install files. To do this open and command prompt as Administrator (Click Start button, type cmd in search box, right click on cmd.exe and select run as Administrator) and run the following command… dism /online /cleanup-image /spsuperseded
This will run for for about 15 – 20 min (even though it says its at 100%) and when its down you should have reclaimed some disk space.
I had an incident the other day where a Windows 7 laptop was having ip connectivity issues as a result of a known bug in Microsoft Windows 7 32bit & 64bit. The bug appears in machines with wireless adapters where a new ip version 6to4 adapter is created on boot up or shutdown. I did an ipconfig on a machine yesterday that showed the machine had 215 Local Area Connections! I had a look around and found what the issue was but everyone who mentioned it said they had to remove each of the adapters one by one. This is fine if you only have 5 or 6, but not 215. Th solution was to use a file called devcon.exe which I got from the Windows Drivers Kit ISO. I have attached a file containing both the 32bit and 64bit executables along with a batch file to show how to execute it. Just extract the the archive to your desktop and run the batch file or alternatively open the command prompt and run it.
Note that you should run either as Administrator otherwise you may get an error saying “No devices were removed” 6to4 Batch Remover
Wow, 5 months since my last post on here. I think thats the longest I have ever gone without posting on my blog in the 5 years I have had it running. I do have a very good reason though. Usually my blog posts are about holidays or events I have been on/to or some funny picture I have made or found but all those activites ceased when I started playing Starcraft 2. I mentioned a while back, my love for Starcraft and my excitment at it impending arrival so when I received the beta key, which I was honored to be included in, I did not really have any spare internet time! And then the retail version which came out a few weeks ago. Basically all my free internet time has been dedicated to either playing it or watching it! I say internet time because this time around I am not going to let it take over my life! 😛 The original Starcraft, which was released in 1997/8 was such an amazing game that it led me to ignoring my college responsiblilies and spending all my time in our college labs gaming! The result was that I had to reapeat a year in college! So I am going to try to control myself a bit bettter this time and hopefully not get fired from work for taking days off or something silly like that! Nooo wayyyyy hosééééé!