Als ik de mails wil afhandelen en beantwoorden in de Roundcube webmail dan worden de mails naar hotmail/live gebruikers niet verzonden en krijg ik met foutmelding weer terug. Hoe is dit op te lossen? Het gebeurd bij alle hotmail adressen.
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hotmail-com.olc.protection.outlook.com[52.101.73.27] said: 550 5.7.1
Unfortunately, messages from [90.145.127.145] weren't sent. Please contact
your Internet service provider since part of their network is on our block
list (S3150). You can also refer your provider to
http://mail.live.com/mail/troubleshooting.aspx#errors. [Name=Protocol
Filter Agent][AGT=PFA][MxId=11BDE8022B460CBF]
[AMS0EPF000001A2.eurprd05.prod.outlook.com 2026-08-07T09:14:31.504Z
08DEF401162B13F0] (in reply to MAIL FROM command)