Asterisk to Switchvox lite to dial out

I have a Switchvox free running as our main pbx and another server running asterisk. I am trying to connect the asterisk server to the Switchvox and us it to dial out.

I did create an extension on the Switchvox for the asterisk server.

Thanks in advance for any help…

Please,
post the relevant details from the configuration file (sip.conf and extensions.conf)
Else it is wild guessing.

sip.conf (on the astrisk server)

[600]
type=peer
context=internal
host=ipaddressofSwitchvox
secret=1234
mailbox=600@default
nat=no
canreinvite=yes
allow=all
;allow=alaw
;allow=ulaw
;allow=g723.1
;allow="g729
;allow=ilbc
;allow=gsm

not sure about the extensions.conf file

Using a call file I want the asterisk server to connect the the switchvox (free) server and dial out to a specif phone number.

The switchvox server has the extions 600 set up though the GUI