Overview 

This tweak can be added into the XCAPI¹ Configuration for the controller being used.

Below is a list of possible issues it may address:

• Faxes are failing to send intermittently. 
• Inbound faxes from the remote site are being received, but when trying to send an outbound fax, an error is encountered: Invalid Message from the XCAPI Line Monitor.
• The Faxmaker outbound via XCAPI fails.

This article provides the steps on how to add the tweak to the XCAPI configuration.

Process

Note: Ensure to list all the changes being made as these changes may cause configuration instability.

1. Open up XCAPI Configuration.
2. In the top menu, select View and click Expert F8.
3. Expand Controller.
4. Expand the controller being used.
5. Expand Tweaks.
6. Select Common.
   
   
   
   
7. In the left box, type in SOFTFAX_REJECT_T38.
   
   
   
   
8. In the right box, type in 1 (1 activates the tweak rejecting T.38 re-invite).
   
   
   
   
9. Open the Start menu and begin typing services.msc then click on Services.
10. Restart the XCAPI services.

Confirmation

This tweak causes XCAPI to send a 488 not acceptable response to a re-invite for T.38 if XCAPI is set for G.711 only.

¹XCAPI is a fax device made by TE-Systems.