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May 4, 2010

Homedrive fails silently to mount at logon (Vista/Windows 7)

After the update to Vista/Windows 7, mapping of the UserHome drive fails silently at logon. All other drive mappings made by a logon script are successful. This happens always if the UserHome is mapped through the AD user-object. UserHome mapping configured by GPO is not affected. There are no error messages logged and it is hard to find a reason for this behavior 🙁

Disabling UAC helps, but should not be the final solution, since it opens up many security holes.

Not really a Citrix problem but annoying if you happen to stumble upon it. Since it took me some time to find a solution, i thought it might be a good idea to post it here.

The following registry key allows again for a successful UserHome mapping:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System]
“EnableLinkedConnections”=dword:00000001

The original solution has been posted here.

Regards
Ecki

June 18, 2008

IE kiosk mode

I recently had a customer that wanted Internet Explorer to be published as a locked down version without toolbars and userinterface. The goal was to publish a browser based application to allow for a smart card rollout and not allowing users to browse away from this site. The search for a solution was harder than expected.

The solution most frequently found with Google was the built in “kiosk mode” of Internet Explorer. This mode can be activated by appending the parameter -k to the IE shortcut. For more details see http://support.microsoft.com/kb/154780. In this mode the IE starts in full screen mode, but without the ability to access the navigation panes, toolbars and menus as it would be possible when switching to full screen view by pressing F11. To end such a session, the user is forced to use the Alt. + F4 hotkey and all navigation in IE has to be done through hotkeys too. Not the solution we wanted for standard users 🙁

The next approach were Microsoft Group policies, but they too had too many constraints and issues. One issue here was, that there is no way, to hide the standard toolbars through group policies. It would have been therefore inevitable to manipulate the HKCU branch of the users registry at logon. This is a subject, where the otherwise “overloaded” IE policies are not detailed enough 🙁

The solution came through a VBS object. Internet Explorer can be addresses and controlled through VBS. This gave me the possibility to adjust the user interface of the IE and to hide all toolbars, navigation panes and menues, without disabling basic functionality. The following code starts IE with a predefined URL and makes it much more difficult for users to break out of the predefined environment 🙂

DIM IE
Set IE = CreateObject("InternetExplorer.Application")
IE.Navigate "http://this.is.the.url.to.be.shown"
IE.Visible=True
IE.Toolbar=no
IE.Menubar=no
IE.Statusbar=no
IE.Width=750
IE.Height=600
IE.Resizable=yes
'IE.Top=5
'IE.Left=5

The entry IE.Navigate stands for the target URL. Take care that the whole URL is surrounded by double quotes. Optional parameters are for the windows size (IE.Width/IE.Height) and the windows position on the users desktop (IE.Top/IE.Left).

IE kiosk mode

This script works perfect under Windows XP and 2003 Server. With Vista and 2008 Server administrative privileges are required!

Regards
Ecki

July 17, 2007

LANMANServer and LANMANWorkstation Tuning

I recently stumbled across this realy good article about terminal server tuning. This article introduces and explains all the relevant LANMANServer and LANMANWorkstation parameters and registry keys.

Following that, the article discusses the potential optimizing actions and their risks and provides even an ADM template that allows to tune your environment through GPOs.

The complete article can be found here.

Regards
Ecki

March 28, 2007

Remove Outlook Express from the start menu

If you have ever published a terminal server desktop, you have seen this happening almost for sure. Even if there is no Outlook Express icon in the All Users or Default Users folder, the icon appears in the start menu after a user logs on for the first time.

Why is this happening? And much more interesting, how can you avoid this?

To delete the icon from every users profile is not a viable option. So it’s best to look for the root cause of this problem. As often, the solution can be found in the registry.

Below the key:

HKEY_LOCAL_MACHINE\Software\Microsoft\Active Setup\Installed Components\{44BBA840-CC51-11CF-AAFA-00AA00B6015C}\

you can find a REG_SZ entry with the name “StubPath“. If you delete this entry, the terminal server will never again create this icon at user logon. Existing icons however will not be deleted.

A post in the DCUG describes a similar procedure but simply renames the entry to “HideStubPath“. The effect is the same, but it is much easier to revert back.

Regards
Ecki

March 14, 2007

Registry Scan (Watermark) for CAG 4.5.x Advanced

Most people who know Citrix Access Gateway (CAG) with Advanced Access Control (AAC) for a while, especially version 4.2, know the “Citrix Watermark” End Point Analysis Scan (EPA Scan). A possibility to configure the security group membership of a PC withe a simple registry key. In contrast to MAC or Domain filters, this scan made it very easy to change the security context of a PC, very handy for product demonstrations, where you want to visualize different access scenarios.

The update to AAC version 4.2.5, eg. version 4.5 introduced a massive change for EPA Scans. Since then, every EPA Scan has to be signed, which renders the unsigned “Watermark” scan worthless. Every EPA Scan delivered with AAC 4.5 is now already signed by Citrix and if you try to create your own EPA Scans, you have to sign them too and build your own specific EPA Scan MSI package. Lots of customers try to avoid this effort and the costs associated with signing certificates. For Citrix partners, trying to build just a demo site, the effort and the costs are too high as well. If you do not intend to spend money on Custom Scans for example from EPAFactory, you are stuck with the scans provided by Citrix:-(

I will therefore show a way, how you can accomplish a working registry scan with the means provided by a standard setup of AAC. Most EPA Scans do in fact nothing else than reading predefined keys in the registry of the client PC. Therefore almost any EPA Scan can be used as registry scan. As an example i will use the “Citrix Scans for Windows Update” shipped with AAC. This scan reads on a client PC recursively all keys beneath:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\

and reports back the KB-numbers found. It must be pointed out, that keys directly below the “Updates”-key are NOT delivered back to the AAC server. You should therefore use an existing key like “SP2” to create your own KB-number key. Knowing that, it is fairly simple to create your own registry scan. A detailed description with screen shots of this process can be found here (german only).

Regards
Ecki

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