HI ALL,
IN MY PROJECT I AM NOT ALLOWED TO USE ELBOLET.
WHEN I USE THE TAP OPTION, EVERYTHING SEEMS TO BE CONNECTED, BUT WHEN I TRY TO CREATE ISO, I GET AN ERROR (DISCONNECTED PIPE).
ANY IDEA WHY?

Which version are you using and what component are you trying to Tap to the elbow ?

Setting the mainsize to the tap size, running the TAP command, selecting the elbow and attaching a nipple to the tap is working on this end.

i want to add a vent pipe on the elbow, i not allowed to use elbowlet

When you add the TAP, make sure to use the EndPoint Osnap that finds this corner connection point.