External application

When opening a document there are two approaches to configuring in what application the file should be opened and if any scripts should be ran upon opening the document. This does not include features like document property mapping, pdf plot settings and such that are common for both approaches.

The approach using Windows Scripting Host have been around the longest but is also the slowest and if there is a malconfiguration it has less informative error messages. Using vbs is getting out of date and sometimes security software blocks it or causes long delays causing opening documents to fail or feel slow.

Support for using External application was introduced in version 11.2 and is both quicker and more stable. Latest release at the moment is 19.0 and though both approaches are still supported we have for years been referring new customers to using Extenal application. Support for vbs in document start have not been discontinued but we recommend that customers still using vbs-approach document starts to change to external application for faster and more reliable performance.

Further reading about Document start is found in MasterExplorer > Help. If you have any questions please contact our support team.

Language settings and AutoCAD

It has been brought to our attention there is another problem with AutoCAD and Windows language settings. There is a new language setting in Windows and AutoCAD does not support having it activated.


AutoCAD is unable to start. The following error message appears.

Exception in vl.crx ARX command

Exception in vl.crx ARX command


To solve this problem go to Windows settings for Region and Change system locale…

In the Region Settings dialogue you uncheck the option Beta: Use Unicode UTF-8 for worldwide language support.

Further reading

The vl.crx-problem is described in short above. In Autodesk Knowledgebase there is a full description.

Recently we wrote about AutoCAD crashing upon start with error “VLISP internal error: Unhandled exception on init”. Our solution was to rearrange the Windows language priority so that there no longer was a red warning icon showing. Autodesk posted a workaround to that problem. The same/similiar problem also have a another article in their knowledgebase with solution same as above.

In short you should be wary about changing language settings as it might break things.


A recent Windows Update in regard to .Net have disabled a setting that used to be enabled per default and is required for the product suite to run properly. If you experience strange behavior probably already at initializing the product there is reason to suspect you might have received this update.

Solution is to reconfigure your system so that required feature is Enabled.


.Net > WCF > HTTP-Activation

This setting must be enabled.

Note that up to date single license users do not need to rectify this as systems that have Internet Information Services (IIS) installed support HTTP-Activation even if the feature is disabled.

In case your version of Windows does not show this feature in the Windows-features dialogue one can use PowerShell to check if it is enabled with a command such as the following.

Get-WindowsOptionalFeature -online -featurename *http-activation* | format-table -AutoSize