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The connector supports version 5.X 7 of Confluence.

General 

Troubleshooting

Problem

Solution

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Problem

The connector cannot login with proper credentials

Solution

This can be caused by the captcha settings of the Confluence server, please check the official documentation about captchas and add an exception for the user configured in the connector

https://confluence.atlassian.com/doc/configuring-captcha-for-spam-prevention-169970.html

https://confluence.atlassian.com/doc/configuring-captcha-for-failed-logins-216957808.html

After changing the configuration and doing a manual login the server the issue should be fixed.