Update: It used to be that rebooting the system would fix the issue temporarily; I rebooted the unit this morning and confirmed that the SPRE command is still not working. I get a fast busy signal when using *207 + Dial.
A quick search for "SPRE" doesn't have any hits or show this fixed in any recent release notes. It sounds like a bug, but may be fixed and not documented under "SPRE" or the release notes for the version where it was fixed may have aged off. A4.08.00 is at least a year and a half old and not even on the Adtran download site any more.
I'd upgrade to a later extended maintenance train like R10.5.3HA and if this doesn't fix it open a support case with Adtran.
I would also suggest a firmware upgrade. You will most likely need to upgrade phone firmware too. The release notes for each version detail what phone firmware is required. If the issue happens again on the new version we would need to see the output from a debug voice verbose and a debug sip stack messages, both running at the same time in the same when the issue is recreated along with the running configuration taken from the unit after the firmware upgrade. You can submit those in a reply if you remove all sensitive information (passwords, public IPs, phone numbers, employee names, etc) or you can submit them to our FTP site with the instructions below:
Open Internet Explorer web browser on their PC
Type the following URL: ftp://ftp.adtran.com
Press the Alt key, click View, and then click Open FTP Site in Windows Explorer
Double-click the "Incoming" folder
Drag and drop files from PC into the Internet Explorer window
Reply to this post with the exact filenames used so we can retrieve the files
If the issue is resolved, please come back to this thread to provide an update so others can benefit and select any correct or helpful answers from the replies.
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