A few things I would check:
1.) Can you ping the HipChat server from your machine (hipchat.com for HipChat Cloud or your FQDN for HC Server)?
2.) If on HipChat Server, verify that you have the correct ports opened per HipChat Server System Requirements: https://confluence.atlassian.com/hc/system-requirements-for-hipchat-server-606306343.html.
3.) Are you using a proxy in front of HipChat? Can you verify 443 https in/outbound to the site from your machine?
4.) If you're still having an issue, please reach out to HipChat support at support.atlassian.com and elaborate as much as possible what you are seeing.
HipChat Server Support Engineer | Atlassian
Earlier this year we made the difficult decision to discontinue our team messaging tools, Stride and Hipchat. The end of life date for Stride and Hipchat Cloud is quickly approaching - February 15, 2...
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