Atlassian Companion App is installed but Confluence prompts it to be reinstalled when you click "Edit with"
Platform notice: Server and Data Center only. This article only applies to Atlassian products on the Server and Data Center platforms.
Support for Server* products ended on February 15th 2024. If you are running a Server product, you can visit the Atlassian Server end of support announcement to review your migration options.
*Except Fisheye and Crucible
Problem
With the Atlassian Companion App already installed and running:
Click on an attachment
Click on "Edit with"
This causes Confluence to present you with a screen that prompts to "Download the Atlassian Companion app to edit this file with a program on your computer, then automatically re-upload it." even though the Companion App is already installed.
Diagnosis
Environment
Confluence is running over HTTPS
- Browser is Internet Explorer or certain versions of Firefox
Cause
- The companion app uses a publicly accessible domain atlassian-domain-for-localhost-connections-only.com which resolves to 127.0.0.1 in order to make a Websocket connection over SSL to the local machine which is running the companion app. Internet Explorer requires this domain to be in the Local Intranet zone and to bypass any forward proxy. Browsers like Chrome don't need this because they treat localhost as a trusted domain already.
- Affected by Can’t edit files in Confluence Server using Atlassian Companion app in Internet Explorer, Edge, Firefox, or Safari
Resolution
- Add the atlassian-domain-for-localhost-connections-only.com domain to Internet Explorer's Local Intranet zone
Add the atlassian-domain-for-localhost-connections-only.com domain to the exception list of any forward proxy between the workstation and the Internet
- Follow the workaround of Can’t edit files in Confluence Server using Atlassian Companion app in Internet Explorer, Edge, Firefox, or Safari