we are unable to add new customers.

[martin_berra]

whatever the email, same error 

- (Email address is not valid)

any solution?

Thnks

[A A Ron Geister _Trundl_ · Accepted solution]

Welcome @martin_berra  I hope all is well and you find your answers here in the community. 

Do you happen to have a screenshot of the error. I am also wondering are they external customers to your service projects or are these external customers you are trying to add. There is some new configuration that can be applied at the "system" settings level. 

I would love to help if you can show me the error and how you are adding users. 

[martin_berra]

thanks for your help, here is the screenshot

[A A Ron Geister _Trundl_]

In the Admin Settings in the top right corner "COG" click on that and select "Product"
Then select "Customer access" In the checkbox External I think is what you are missing. Check that and then try again.
I believe you have to authorize external customers be added. I would also check by using a person email to see if that will work. The domain has to be a valid domain also of you can get the same error. 

[martin_berra]

thank you very much for your help. 

[A A Ron Geister _Trundl_]

You are very welcome and glad the suggestion helped you out.