Nextcloud 19 Mail

Hi I Updated Nextcloud to 19, now Nextcloud Mail App can’t connect to IMAP Server anymore.
Only connection local with smtp on port 25 is going to work.
I look and there no incoming connections from Nextcloud to my Private Mail Server.
I Use an Synology before the Update everything was right.
I have tried different Options div. Restarts but the Same Problem.
In Nextcloud Log is only the message can’t connect.
Anyone with the same Problem and a solution for me?

Self-signed cert, possibly? Then check https://github.com/nextcloud/mail/releases/tag/v1.1.4

Thx for fast reply, I have check it with this Version but only the same.
I have check connection with openssl it work fine.
Only connection from Nextcloud to my Mail Server don’t work to webdav no Problem
In Nextcloud 19 any tricks for htaccess or config.php that could me help ?
Because is there an issue while mail and nextcloud is hosted on Same Server ?
Nextcloud is on a Virtual Host.
SSL Certificate is Working without problems. I have a Certificate for all Domains on my Synology

From what you are describing the setup sounds sane. Is there a possibility that only php can’t connect? Or that php uses a different certificate chain for SSL and therefore is unable to verify your cert?