Removing Silverlight When it Fails to Uninstall


I was having problems removing Silverlight 3 from the Add/Remove Programs feature. These are the steps I followed to get rid of it and upgrade to Silverlight 4.

Step 1 – Create a new system restore point (optional)

Click Start, All Programs, Accessories, System Tools, and then click System Restore. The System Restore Wizard opens. Click Create a restore point, and then click Next. In Restore point description box, type a description. Note:  The date and time are automatically added to your restore point. Therefore, you dont need them in your description. Click the Create button.

Step 2 – Try Add/Remove Programs Again

In the control panel find Add/Remove Programs or Programs and Features whichever one you have. Uninstall Microsoft Silverlight if it is shown as installed by clicking on it and then clicking Uninstall or Remove.

If you still get an error message (for example a dialog appears saying that the msi file cannot be found) just continue on to the next step.

Step 3 – Mess with things

Click on Start > Run  Type in cmd and select OK. From the command prompt screen run the following commands

reg delete HKLM\Software\Microsoft\Silverlight /f

Close the command prompt window.

Rename the C:\Programs Files\Microsoft Silverlight folder to C:\Programs Files\MSSL

Goto Start >Run and type Regedit. It will open registry editor. Highlight My Computer. Click on the File menu and select Export. Make up a file name and save the file (on the desktop for example).

In the registry editor navigate to HKEY_CLASSES_ROOT\AgControl.AgControl Expand AgControl.AgControl

Select the CLSID key. Edit the (Default) value by right clicking and selecting modify and change it to {DFEAF541-F3E1-4c24-ACAC-99C30715084A} then click OK

Select the CurVer Key and change the (Default) value to AgControl.AgControl.1.0

Navigate to HKEY_CLASSES_ROOT\Installer\Products  Find the key called D7314F9862C648A4DB8BE2A5B47BE100 and rename it to OLD_D7314F9862C648A4DB8BE2A5B47BE100

Step 4 – Try to install Silverlight again

Overview of Microsoft Windows Active Directory

What’s Active Directory?

Active Directory is the directory service included with Windows servers. It stores all the information you would need to manage a windows network, for example user accounts, file servers and printers, and the rules about who’s allowed to do what (Group Policy Objects).

You might have noticed the word Object pop up there in GPO. The data stored in this ‘Active Directory’ is organised into things called objects. The Active Directory Schema is where you define what kinds of objects you can put in your directory. If you’ve never heard of objects and schema, the concept is quite similar to XML schema.

It’s a confusing abstract term “object”. In my head, I substitute object with “thing”.

Lots of Confusing Words

In Active Directory you have to organise all your information into objects. These objects can be organised into a structure. So Microsoft made up all these things to help you structure your directory, and here they are.

All your computers are probably networked. So you normally look at a manageable chunk of your system, for example by looking at your local area network. You then create a Site and lump in everything to do with your LAN in there. Site means your physical site.


You put all your users, printers, email addresses, databases etc. into domains. You can make one domain and use it over different sites or locations. So if your organisation has two main sites in two cities, you can simply use one big domain.

Domain Controller

Something real! This is your active directory server that keeps a copy of the domain directory. You can have more than one domain controller in a domain. However a domain controller can only service one domain. A domain controller is the server that checks your password is correct when you login etc.


When you create a hierarchy of domains, you have a… tree! By making a tree of domains in your active directory. This is actually quite a nice simple idea, and it’s tied to DNS a bit. Imagine you have a domain name is the top level domain or main site, and is my bit. There are lots of ‘child’ domains under for everybody else who uses wordpress like, everyone looks after their bit. So you can think of it like a tree, with at the root, and cyleft, and torinelson as two branches coming out from there, among others. That’s what your tree is, a domain tree helps you organise your directory.


Trees are fine, but Forests? If for example, you had as a domain tree and as another domain tree, you can make a forest! Now you can share Active Directory Schema, and communicate between trees etc. Both trees trust each other, so if you login to one tree, the other tree trusts that you’re a real user who gave the right password (otherwise you’d need to login to both trees)

Organisational Unit (OU)

You make OUs to help you administrate your network, so you can have lots of separate administrative groups to manage your actual (huge) windows network. You can put OUs in other OUs in a nice tree structure as well.

Global Catalog

If you have more than one domain in a forest, you need a global catalog so that you can login to the network no matter which domain controller you are using. That’s what the global catalog does, it stores all group membership information. This is usually stored on a global catalog server and cached on each domain controller.

Users and Groups

When you login to your Windows computer, you can login in two ways. One, your username and password is stored and checked on your computer, known as a Local User Account. The other place you can store and check your password in is the Domain Directory on a domain controller, making it a domain user account. This means that you can have local administrative accounts that can control your computer, and domain administrator accounts which let you change things in the domain, tree or forest.

You also have user groups. These are just to lump users and things (like printers) together. You can have different types of groups, some are limited to a single domain, and some groups let you grant permissions and access to anything in any domain in the forest.

Group Policy

It should really be called Grouped Policies. A GP is a collection of settings that tell you how programs, Windows etc. work for users and computers in the active directory. You save them in a Group Policy Object and apply it to domains, sites, OUs etc. It doesn’t mean that you create some policies or settings that you apply to a group. GPs are not applied to groups, you apply them to domains, or OUs or whatever. Stupid I know. You can have local GPOs for your local computer and domain policy GPOs which get applied to every user in the domain.

Tools & Utilities

Here’s a list of tools and utils used to administer/diagnose active directory. If you want to know more, just ask:

  • netdiag.exe
  • dcdiag.exe
  • ntdsutil.exe (NT Directory Service was the old name for Active Directory type stuff in years gone by)
  • dcpromo
  • gpedit.msc
  • netdom
  • dsastat
  • repadmin
  • dsadd, dsmod, dsquery
  • whoami
  • runas
  • gpresult

There are lots of details about Active Directory which will bore the hair off your eyebrows but I have already had enough.

Windows XP Disk Cleanup Takes A Long Time To Start

Microsoft Windows XP comes with a utility called Disk Cleanup. You can find it by going to:

Start Menu -> All Programs -> Accessories -> System Tools -> Disk Cleanup


If Disk Cleanup is taking an annoyingly long time to start up because it is ‘scanning for old files to compress’, you can force it to stop this scan. All you need to do is modify the registry. Using regedit.exe or similar tool, browse to this key:



Find the ‘Compress old files‘ registry key and rename it. Save and close.

You can find Microsofts knowledge base article on this here:

Web hosts

I use! Powered by 100% wind energy!

This post was prompted by a comment on one of the articles, so I’ve moved it to it’s own spot to write a little about it

I want to find a totally free hosting service that is ok to accept CGI. Do you believe that I can have a wonderful host or better a first-class free hosters database or something like that for what I want ?? ps: Do you know free no ads hosting ?? How have you built your blog ? — Quentin Bonnes

OK, you can have wonderful host, a fantastic host, even better, a first class, top notch, top of the line, triple-a host. But I don’t think you can get one for free.

Do I know any ad-free, cost-free hosting service? Nope, most have ads.

How have I built my blog? Why, that’s easy. All you do is go to and hit the big orange button that says sign up. It’s a quick and easy and free. The editor you get to write your blog with, is amazing – very easy to use.

If you’re looking for hosting with features like CGI script support, databases etc. I’d go for a ‘cheap host’. They’re usually around £3-5 a month. The web servers might be a bit slow, but they’re good value for money.

If you’ve found a web host you like (or not) get in touch!

Desktop PC hardware problems

Situation: Desktop PC stops working for no apparent reason. Doesn’t power on. Tested power supply, power button, CPU, RAM, all fine.

Solution: CMOS battery. PC would boot if the battery was removed. If it is inserted, system doesn’t power on. Replaced battery, but the problem persists. Perhaps there is corrosion somewhere near the battery socket which causes this. I just left the battery out.

When trying to update a password, current password is not correct

What The Error Message Said..

When starting windows you get this message at the login prompt:

“When trying to update a password, this return status indicates that the value provided as the current password is not correct.”

Why Did This Happen?

Most likely, I was trying to login to a computer and recover the password.


Replace the SECURITY/SAM file that lives in C:\WINDOWS\system32\config


To do this you need to access C drive in your computer without running Windows that is installed on that C drive. You can start the computer using a boot disk such as BartPE (see Google for detailed instructions). You can also move the disk to another computer and make the changes on that computer (see Google for detailed instructions).

Where do I get the SECURITY and SAM files?

If you are pretty stuck, try getting these from a fresh install of the OS you are working on (most likely this was Windows XP). Otherwise you should have a backup of these files since you were smart and backed them up before you messed about with them.

Cloning when you’ve forgotten to sysprep

If you need more help with any of this post please leave feedback


Cloning a hard drive means making an exact copy of a disks contents so that you can either backup or migrate your disk. This post is about cloning a windows partition so that you can run it from a different PC with different hardware on it. There is a useful section at the end, which will help you get into windows if you’ve forgotten to sysprep.


An easy piece of software to use is Ultrasoft Snapshot. Then use Microsoft sysprep utility to prepare the system for cloning. Use ‘snapshot’ to clone the partition to a backup hard drive. Restore the backup to a new disk.

If you haven’t run sysprep, and you no longer have access to the old machine, there’s some help to get you going in the trouble shooting section.

Microsoft sysprep

Microsoft have a page on sysprep. I forgot to use sysprep (hence this post) so you’ll have to google this section. Good Luck.

Ultrasoft Drive Snapshot

Use the ‘snapshot’ software from a startup disk in your original machine (eg bartpe) or by installing the original hard drive in another pc (let’s call it the host pc) and running ‘snapshot’ on the host machine. This is required because snapshot needs exclusive access to the source hard drive partition (the one you’re cloning), so you can’t be running windows off the drive you’re cloning whilst cloning.

You need the same amount of space free on your target hard drive partition as the source partition. If you have alot of free space on the source partition, it might help to resize it, eg using Partition Magic.

Use the ‘snapshot’ program to extract the cloned partition to the target hard drive. You can then boot into your target machine and finish. If you have trouble booting, mark the partition as active (can be done from boot cds, or installing drive in different machine and using the computer manager from the windows control panel.) Make sure the MBR has a working boot loader (eg use fixmbr from windows installation cd restore mode to reinstall bootloader.)

Troubleshooting ie forgetting to sysprep

If you cloned the partition and tried to boot it without sysprep’ing before cloning you will probably get problems starting the computer. It either restarts endlessly, or you get a blue screen (STOP 0x0000007B messages indicating problem with boot drive).

This usually happens because windows has problems starting in the new machine, as it is still setup for the old machine. One way to solve this problem is to install windows on your target machine in a new & empty partition. Then you need to copy over the system/sam/ security files from C:\windows\system32\config over to the problematic install. This will effectively overwrite the data windows keeps about the system hardware. I already had a windows installation on my target machine, so I copied these files over, and in my case this allowed me to boot into the cloned windows partition!

The only problem then remaining is that you might have registry entries in your old config files that are required by the software you had installed. These have to be manually sorted out by mounting the hives in regedit and copying the required data out. This is possible for a few registry entries (eg Windows Services entries etc.) but it’s probably too much hassle otherwise.


My problems were solved after copying over the configuration files, and fixing a few registry entries.

If you have time, instead of overwriting the entire SAM/SECURITY/SYSTEM hives, only overwrite the sections containing hardware information. Which sections are those? No idea, you’ll need to find out. Copy out enough registry entries to get it to boot (may only be those regarding chipset/graphics card/hd.)

Otherwise, find a guide on sysprep’ing after cloning and try that. Oh and let me know if that works.