Category Archives: Computers

Mac OS X and Windows

Can’t Find Groups Management On Windows 7 Home and Vista Home Editions

How to Manage Local Groups on Windows Home

Ever helpful, Microsoft provides a GUI interface for managing users and groups on Windows. Unless you have a Vista home edition or a Windows 7 home edition, in which case you can’t find the interface to manage groups because it isn’t there. You can however manage groups very easily from the command line.

Manage Windows Groups from the Command Line

Simples. Find Command Line in your Start Menu Programs so that you can right-click on it and choose ‘Run As Administrator’

net localgroup /?
net localgroup MyNewGroupName /Add
net localgroup MyNewGroupName MyFirstUserName /Add
net localgroup MyNewGroupName MySecondUserName /Add
... and so on

And voila. You can now set security on folders in explorer, and use your new group to grant access.
If your Windows permissions are not working after you’ve granted new permissions, the usual trick is to lock and unlock your session (Start Menu — The Power/LogOff/Hibernate/Lock/Sleep button). Failing that, log out and back in again.

Net Localgroup Reference

Is here:

iTunes Home Sharing Not Working

There’s a handful of reasons that can cause this. The probably definitive list can be found by combing the apple tech support discussion thread for it at
I recommend you start at the end of the thread where you’ll find the answers rather than at the beginning of the thread where’ll you find the kind of posts that people write when they’re tearing their hair out because their shiny expensive toy DOESN’T WORK.
The one that worked for me was:

  • Restart the windows Bonjour service. If you don’t know how to do that, just restart your computer.
  • The other popular one is: “Sorry bud, you need a new router.” Or if you’re ‘lucky’ just a firmware update (Have you ever tried updating your router firmware? I did it once). You can’t win then all.

A Very Small Editable PDF for Testing

A Small PDF

Ever wanted a small PDF file, or to tweak your own PDF for testing? Below is a very small PDF which you can paste into a text editor and save as MySmallPdf.PDF.
Two things are easy to edit:

  • The page size. Look for the line /MediaBox [0 0 612 144]. Leave the first (0,0) pair and edit the (612,144) to be (width of page,height of page) in 1/72ths of an inch.
  • One line of text. Look for the line (This is a small text editable pdf) Tj and replace the text with your own.

This is particularly helpful if you are testing or itextsharp or some other PDF generator or API, and you want a couple of small identifiable test files to play with.

The Editable PDF

1 0 obj
<< /Type /Catalog
/Outlines 2 0 R
/Pages 3 0 R
2 0 obj
<< /Type /Outlines
/Count 0
3 0 obj
<< /Type /Pages
/Kids [4 0 R]
/Count 1
4 0 obj
<< /Type /Page
/Parent 3 0 R
/MediaBox [0 0 612 144]
/Contents 5 0 R
/Resources << /ProcSet 6 0 R
/Font << /F1 7 0 R >>
5 0 obj
<< /Length 73 >>
/F1 24 Tf
100 100 Td
(This is a small text editable pdf) Tj
6 0 obj
[/PDF /Text]
7 0 obj
<< /Type /Font
/Subtype /Type1
/Name /F1
/BaseFont /Helvetica
/Encoding /MacRomanEncoding
0 8
0000000000 65535 f
0000000009 00000 n
0000000074 00000 n
0000000120 00000 n
0000000179 00000 n
0000000364 00000 n
0000000466 00000 n
0000000496 00000 n
<< /Size 8
/Root 1 0 R

The PDF ISO32000 standard

The PDF reference is available for free from Adobe at The one you want is the copy of the ISO reference at

I want to set a Windows Environment Variable for my whole user login session

Use setx to permanently set an environment variable

If you’ve used windows environment variables at all, you’ve probably wished you could set them in a command window for use in another program.
You can’t change the environment of an already-running program – the environment is copied when a program starts – but you can set environments values for your user session that will be picked up by any new programs you launch with setx:

setx myvariable thenewvalue

Much easier than right-clicking to get to My Computer properties.
setx /? will also tell you about setting permanent, machine-wide and remote machine environment values.

setx comes with Windows 7 or in the Windows Resouce Kit.

How to unset a variable set with setx

setx myvariable ""

See for more details.

A no-code routing service using .Net 4 on IIS

A year ago I was working with Waheed Hussain who pointed out that the .Net framework includes a Routing namespace which allows you to implement a service router with zero code. Literally. It’s an IIS application with no code, just a web.config. Here’s an example:

< ?xml version="1.0"?>
				<filter name="MatchAll" filterType="MatchAll" />
				<filtertable name="MyFilterTable">
					<add filterName="MatchAllFilter" endpointName="MyDestinationEndpoint" priority="0"/>

			<service behaviorConfiguration="routingConfiguration" name="System.ServiceModel.Routing.RoutingService">
				<endpoint address="destinationUrl/" binding="basicHttpBinding" name="routerEndpoint1" contract="System.ServiceModel.Routing.IRequestReplyRouter" />

			<endpoint name="MyDestinationEndpoint"
					  contract="*" />

				<behavior name="routingConfiguration">
					<routing routeOnHeadersOnly="true" filterTableName="MyFilterTable" />
					<servicedebug includeExceptionDetailInFaults="true" />
					<servicemetadata httpGetEnabled="true"/>
				<behavior name="clientEndpointCredential">
						<clientcertificate storeName="My" 
                               findValue="MyClientCertificate" />

				<binding name="basicHttpBindingWithClientCertificate">
					<security mode="Transport">
						<transport clientCredentialType="Certificate"/>

		<!-- The clever bit - activate with no code needed -->
				<add relativeAddress="" 
             service="System.ServiceModel.Routing.RoutingService, System.ServiceModel.Routing, version=, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>

		<compilation debug="true" targetFramework="4.0" />

			<servicepointmanager expect100Continue="false" />