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• Regex pattern: ^.*\@(?'domain')

• Replacement pattern (vervangingspatroon): employee@{domain}

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Attribute overview

The result of the attribute configuration looks as follows, please pay attention to the proper amount or lack of quotes:

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Submit the intake form 

Please complete the form ‘Technisch Intakeformulier govconext’ with the metadata-URL and default schacHomeOrganization and the other required information and send it through the govroam ‘klantportaal’ and/or ‘tech@govroam.nl’. 

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Since govconext is built using OpenConext software which is also used for SURFconext, you can find additional information if you search for SURFconext, specifically:
Handleiding Azure AD als SAML Identity Provider in SURFconext - SURFconext - Get Conexted - SURF Wiki - https://wiki.surfnet.nl/  

Also, Microsoft provides an extensive article:  
https://learn.microsoft.com/en-us/azure/active-directory/saas-apps/surfconext-tutorial