Hi @mdavila - This error message is stating that the package you have installed (BumbleBee) has Python nodes in it that are targeting an older version of Python - IronPython2.
We have removed that version from out-of-the-box Dynamo as it is no longer supported by the authors meaning it will no longer receive security or bug patches. The team creating IronPython2 have moved on to IronPython3. The onus is now on every user to download IronPython2 if they feel it appropriate to do so for their own set-up.
The default version of Python in Dynamo is now CPython3, but you can still download either IronPython2 or IronPython3 as packages from our Package Manager.
In short, you will need to download the IronPython2 package to keep BumbleBee working as designed, and can easily do so 
After you do that, you can click the “Do not show again” tickbox and not have to worry about it.