Conda install or update hanging with an error related to

If you are trying to install a conda package (cmake, numpy, etc.) or update an existing package, but get an error message with “” anywhere … please edit your .condarc file (usually in your home directory) to remove the channel.

Example of this error when installing cmake:

Fetching package metadata .......
CondaHTTPError: HTTP None None for url <>
Elapsed: None

An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.
ConnectTimeout(MaxRetryError("HTTPConnectionPool(host='', port=80): Max retries exceeded with url: /conda/dev/osx-64/repodata.json (Caused by ConnectTimeoutError(<requests.packages.urllib3.connection.HTTPConnection object at 0x11367e350>, 'Connection to timed out. (connect timeout=60.0)'))",),)

The problem is that lsst_sims packages used for a while for conda installations, but this is now obsolete. If you have an old version of conda which you used to install packages from this location, then you might still have in your .condarc file. However, because we no longer use, the URL offers no response and will timeout. Simply remove from the list of channels and you are good to go.