Does anyone kno how EX90 ver TC 4.1 register CUCM 7.1.5 ?
CUCM 7.1.5 version can not upgrade, you can play what patch?Orthe EX 90 can be upgraded to version support CUCM 7.1.5.
Is there a perfect solution?
The native registration support for Ex90 and lot of other video endpoints has started with CUCM version 8.6 and later.So you can try registering but that won't be a native SIP registration.
You can try below steps for the registration.
If the above doesn't works and if you are only looking for calling purpose you can also go with the SIP third party (BASIC).
adittionaly check another thread realted to your problem.