We recently upgraded our UC520 from V8.2 to V8.6 (uc500-advipservicesk9-mz.151-4.M5). MWI was working fine but no longer does since the upgrade. I've been through the config and it all looks fine, I can see no changes to cause the issue.
I cannot find any know issues with the upgrade process we followed.
I should state I did not install or upgrade this system (I have inherited it) and I would expect there to be slightly different config to what is in place but I've only ever dealt with CUCME rather than UC500. I have been informed though that MWI was functioning prior to the upgrade and I did try the following config but this made no difference either:
mwi-server ipv4:"IP Address" expires 3600 port 5060 transport udp unsolicited
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