So today i had problem when my Rainloop webmail gave me the below error
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Solution:
The Solution was simple but it took me sometime to figure out. It was related to SSL
So a quick fix was to go to Admin panel of your Rainloop server e.g https://<yourdomain>/?Admin
After logging in Click on Domains as show below
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Once you click the domain you will see window as show below
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Now click on your domain and you will see window as show below
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Now change SSL/TLS under IMAP to None for the time being and click update. Your should be able to login now.
I think the issue is with SSL Certificate , it should be updated , after update you must revert the changes from None to SSL/TLS.
Thanks,
Salman A. Francis
https://www.youtube.com/linuxking