Zoiper android and iOS not able to accept calls.

Question

All of my zoiper android and iOS clients are not able to accept inbound calls.  This is not an issue that appears on my IP desk phones and ATAs as well as zoiper for windows desktop.  It also not not seem to matter whether the devices are local or remote relative to the pbx.  I receive the following error in my PBX logs:

[2016-09-19 12:46:27] WARNING[2141] chan_sip.c: Retransmission timeout reached on transmission 69f0fa314044f3bd4eb0503043f87f1e@XXX.XXX.XXX.XXX:5061 for seqno 102 (Critical Request) -- See https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions
Packet timed out after 99ms with no response
[2016-09-19 12:46:27] WARNING[2141] chan_sip.c: Hanging up call 69f0fa314044f3bd4eb0503043f87f1e@XXX.XXX.XXX.XXX:5061 - no reply to our critical packet (see https://wiki.asterisk.org/wiki/display/AST/SIP+Retransmissions).

Answer 1

Hi, check whether the account are registered to the server when you are trying to call them. It is possible that you might need to enable the options from the incoming calls section in Zoiper's Settings. Another option is to use TCP as transport type, but the PBX should support it.