Knowledge Base Home

Call Support

Search the Knowledge Base

Skip to end of metadata
Go to start of metadata


Netmail Archive 5.x


The IIS Extensions provide one-click access to a user’s archives from within OWA by providing an Archive link.  Since IIS supports compressed communication with the user's browser, this information needs to be decompressed before being passed to the extensions' ISAPI filter.  If the module which performs this decompression does not run prior to the ISAPI filters, IIS Extensions will not understand the responses and will not be able to provide an Archive link. This article will explain how to ensure the proper sequence of modules in IIS so that the extensions can function properly.


If the Archive button is missing from OWA and restarting the Netmail AWA Remote Provider Service does not restore the button, open the A_log.txt file on the CAS server (usually located in C:\\IISExt).  This file logs all requests received when users click on the Netmail Archive button in OWA.  The following errors are generated in the A_log when the order of execution of the IIS Dynamic Compression Module and the ISAPI filter module is incorrect:


UNZip error: invalid distance too far back

failed to unzip response. Error: -3

not found 'a_sFldId' or 'a_sInbx' in response


These errors are generated because the Dynamic Compression Module must be executed before the ISAPI Module

To address this issue, access the CAS server and Open the Internet Information Services (IIS) manager (part of Administrative Tools). The following procedure will change the Module execution order (refer to screenshot below):

  • Navigate to Server Name > Sites> Default Website
  • In the IIS section, select Modules
  • Once the Modules are listed, go to the Actions area (right pane) and select View Ordered List
  • The modules are listed in the order that they will be executed
  • Make sure that the Dynamic Compression Module is listed above the ISAPI Filter Module so it is executed first.  Use the "Move Up/Down" links on the right to change the Module order:



Once the Module execution order is reconfigured, the archive button in OWA should be visible again and the archives will be accessible.


Help us improve!
Is this article helpful?
Is it well written?
Is the content complete?

  • No labels