Citrix Receiver: You have not chosen to trust “COMODO High-Assurance Secure Server CA”, the issuer of the server’s certificate

Written by Ingmar Verheij on January 24th, 2014. Posted in Citrix

Citrix ReceiverRecently I started using a MacBook to replace my Windows laptop. Since I work as a technical consultant with Citrix products I frequently connect to a Citrix XenApp / XenDesktop environment, amongst other to our lab.

While the installation was straightforward (just go to and click on Download Reveiver for Mac) I quickly faced a dialog telling me I haven’t chosen to trust the CA certificate with no option to solve this…

You have not chosen to trust , the issuer of the server's certificate

Microsoft App-V: Dynamic Configurations or RES Workspace Manager?

Written by Ingmar Verheij on January 22nd, 2014. Posted in Microsoft App-V, Workpace Manager

When you’re using Microsoft App-V 5 to distribute your “virtual” applications it can be cumbersome to apply settings afterwards. With native installed applications you have to ability to update files, registry settings or apply permissions (since App-V 5 always applies default permissions).

Within a virtual application these settings needs to be applied within the virtual environment (often referred to as “the bubble”). Up to App-V 4.x you had the ability to add custom actions in the OSD file, starting App-V 5 this is replaced with Dynamic Configurations.

While Dynamic Configurations are more powerful and flexible then the static OSD files I couldn’t resist to show you how RES Workspace Manager can simplify this.

Citrix NetScaler: Cannot load applet (7u51)

Written by Ingmar Verheij on January 20th, 2014. Posted in Netscaler

Java Update Available

TIP: NetScaler 10.5 uses HTML5 instead or JRE for most configuration features! Hooraaayyy! – link

On January 14 Oracle released Java Runtime Environment (JRE) 7 update 51. Just like previous updates the raised the security level which could potentially break existing applications. We saw the same when they released 7u45, back then I found a more constructive (but complex) solution to solve a problem where the GUI hanged at “Downloading Applet..

Citrix updated their NetScaler software to meet the requirements of Oracle on December 3rd (download, release notes) – I hope that back then you reverted to a more secure JRE. Unfortunately JRE 7u51 gave me again problems, this time the Java Applet could not be loaded.

Citrix NetScaler: DSR, a poor man’s load balancing solution

Written by Ingmar Verheij on January 8th, 2014. Posted in Netscaler

Gartner Magic Quadrant for Application Delivery Controllers 2013There are occasions where you need a good load balancer but don’t have the budget. Microsoft offers Network Load Balancing services (NLB) as part of their Windows server operating systems, but although we’re looking for a cheap solution we try to avoid problems. This is where the Citrix NetScaler comes in. Gartner positioned the NetScaler ADC in the leaders quadrant of the Magic Quadrant for Application Desktop Controllers (for the 7th consecutive year in 2013), proving it to be good solution and a reliable partner. Using Direct Server Return (DSR) mode we can offer a “poor man’s solution”.

In this article I’ll explain why you might (not) want to implement Direct Server Return (DSR), how it works and of course how to configure it!

Citrix NetScaler: Cache Microsoft App-V sequences

Written by Ingmar Verheij on January 3rd, 2014. Posted in Microsoft App-V, Netscaler

Citrix NetScaler: Cache Microsoft App-V sequencesRecently I wrote about streaming App-V 5 packages via HTTP. Using caching in IIS performance can be enhanced while resource consumption on the SMB share are minimized. Since we’re using HTTP for streaming it’s not unlikely a load balancer is used to divide the traffic to multiple App-V streaming servers adding another hop.

When a Citrix NetScaler is used to load balancing App-V Streaming Servers you could use Integrated Caching to cache resources. When resources are cached on the load balancer less network traffic is generated. Integrated Caching is part of the Platinum or Enterprise edition with Caching option.