I need some outside perspective and apricate any help. On an IPO 9.1 with a B159 we cannot make two outgoing external calls and conference them. The system has 14 analogue lines. I have setup the *47 SC on the B159 as well as the 500ms flash time and can easily conference one external and one internal call. The problem is once the first call is connected and the second dial tone obtained, as soon as I dial 9 for the next outside line we receive a busy signal. There is a user short code set (9N) to route calls to an ARS table entry containing a single analogue line used for this phone only (This line is a DID for this extension as well). The table has an alternate route set with priority 5 and wait time off. The alternate route is ‘Main’ a group of many lines none of which were off hook at the time I tried this. Thank you for taking the time to read this and offer assistance.

try this:
https://www.ipofficeassistance.com/setting-up-a-conference-on-a-b149/

Thank you, but unfortunately tried that yesterday with the same result.

Have you unchecked Inhibit Off Switch Forward Transfer in System > Telephony? Have you checked Allow Analog Trunk to Trunk Connect for each line on the Analogue Options tab?

I didn't uncheck inhibit off switch forward. I did allow trunk to trunk connect. I will try this today and let you know. Thank you !

Thank you for all the help! This worked flawlessly, it is greatly appreciated.