Hi @Benoit Patin ,
In order to better solve this issue, I want to confirm the following information with you:
1.Can this user successfully open the hyperlink of the Sharepoint folder shared from other users? Or whether could click the hyperlink in other sharepoint share email?
2.Can the link copied from the source code be opened normally?
3.After receiving the email, are there any warnings or errors?
4.Where did you read this email?
1)If you open the email in outlook client, please try to login to OWA and see if you could click the hyperlink.
2)If you open the email in OWA, please try to change the browser to rule out the browser’s possibility of causing this issue.
According to my test, I have modified Sharepoint’s policy for sharing with external users several times, but still no recurrence issue. I create a new sharepoint site and create a new folder. Then shared the folder to an external user with email, and the user could click the hyperlink normally.
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