Question

How do I resolve a problems with CCE Web Chat and IIS?

Response

The CCE Web Chat involves many components that need to communicate together. When any one of these components do not work a number of errors may be generated in other applications. By analysing these error messages it may be possible to identify the cause of the problem.

Consider IIS 5.0 and its communication with the ISAPI extension (For IIS 6.0 specific information see the related article below). All web chat messages are passed through IIS to the ISAPI extension and then onto the client or Simple Messaging Mediastore via the Web Chat Gateway using polling. If the IIS server cannot load or blocks communication with the ISAPI extension then no messages will be able to be passed.

IIS to ISAPI Extension communication

User Message: QueryAsyncQueueStatus did not return an expected reply. ATWebChatExt.dll might not be accessible, please ensure IIS execution permissions are set for the folder where ATWebChatExt.dll resides.

If the above message appears in the client, then the IIS is unable to communicate correctly with the ISAPI extension. This could be for the following reasons:

• The bin folder where the ATWebChatExt.dll file is contained does not have 'Scripts and Executables' permissions
• Anonymous access is not allowed to the default Chat website
• The path to the ISAPI extension is not correct in your web page- ISAPIDLLPath="./bin/ATWebChatExt.dll";

If these do not resolve your problem, check the IIS logs to see if IIS itself has recorded any issues.

ISAPI Log files

The ISAPI extension also creates its own log files. However sometimes these are not written. This is because the IWAM(IIS Process Account for IIS 5.0) may not have write access to the logs folder. Give this user rights to log folder and a log file should be generated. This will help you with your diagnosis. A log file will not be created if the ISAPI extension cannot be accessed by IIS as in the issue above.

Web Chat Gateway to ISAPI communication

UserMessage:0:ISAPIError:errorNum=0,errorMsg=No control sessions are available to query queue status

If the above error occurs the client application is able to communicate with the ISAPI Extension however the web chat gateway has not been able to open any sessions between the gateway and the ISAPI extension for a given queue name.

This can occur when:

• There is a firewall or antivirus software between the Web Chat Gateway and the IIS server blocking communication.
• The Queue names in Simple Messaging Mediastore do not match the queue names contained in the web page being presented to the customer. The defaults are 'Sales' and 'Services'. Either change the Simple Messaging Mediastore configuration or the web page html code.
• The Web Chat Gateway has lost connection to the ISAPI extension and has not recovered correctly. During a server restart a similar issue can occur due to IIS being slow to initialise, with the Web Chat Gateway driving the CPU to 100%. Both these are known issues and are resolved by applying CCE 2.0.1 Service Pack 1 for Simple Messaging Mediastore, Web Chat Gateway and ISAPI extension.
• The IP address of the Web Chat gateway machine has changed. As a security measure when the ISAPI extension is installed the location of the Web Chat Gateway that the ISAPI extension should communicate with is stored in the registry. If the location of the Web Chat Gateway changes, the registry entry must be changed. This can be found at HKEY_LOCAL_MACHINE\SOFTWARE\Avaya\Avaya Contact Center Express\AT Web Chat Extension however normal precautions should be taken and only experienced people should attempt to edit the registry. Note after  changing the registry IIS will need to be stopped and restarted so that the ISAPI extension is reloaded.
• At times the DHTML Chat window may say 'Intializing.....' forever. This indicates that status messages between the Simple Messaging Mediastore and the Web Chat Gateway is not happening correctly. This usually due to network issues such as a firewall between the Simple Messaging Mediastore and Web Chat Gateway which does not allow MS .Net communication on port 29085. This port will need to be opened in the Web Chat Gateway to Simple Messaging Mediastore direction. Also dual network cards may cause MS .Net issues which will require the server name or IP address to be entered in the ASWebChatGateway.exe.config file
  e.g <channel ref="tcp" machineName="IP address goes here" port="0">
  Note: The parameter machineName is case sensitive and must be entered as shown.
• Simple Messaging Mediastore is not correctly configured with a queue equal to a name and a configuration section with the same queue name e.g.
  
  [Queues for Media Gateway]
  Queue 1 = Technical
  Queue 2 = Sales
  
  [Technical]   - Each queue above must have a section with the same name containing its configuration
  Status = Open
  Privacy = Allowed Mode
  Media Director Queue = Q_WEB

[Sales]
Status = Open
Privacy = Allowed Mode
Media Director Queue = Q_EM_SALES

For information specific to IIS 6.0 (2003 server) please see the related article below.

Applicable to

Avaya Contact Center Express  all versions