External Sharing in SharePoint and OneDrive is changing: What You Need to Know

In an ongoing effort to create a more secure environment by default, Microsoft is introducing an important security update that will affect how external users access content shared through SharePoint and OneDrive. Starting July 1, 2025, any links shared with external users before your organization enabled Microsoft Entra B2B integration will no longer work. This change applies to all organizations that have already enabled or will enable SharePoint and OneDrive integration with Microsoft Entra B2B (Most organizations I have looked into so far). External users trying to use old links will see an error message saying the organization has updated its guest access settings. To regain access, the content must be reshared. Highlights of how the change affects organizations who have enabled B2B: All external sharing will require guest registration. External users must be added as guests in your Microsoft Entra directory. Access will be managed through Microsoft Entra B2B Invitation Manager. T...

Important certificate note to self

I've been having issues on a server, where I was supposed to create a secure channel (tls) to a remote server for synchronizing the exchange free/busy information on users. I long suspected it to be certificate related, but I always ended up by turning ssl of (thus running unencrypted). I thought I had it all done right, when importing the root certificate of the CA to the trusted root. But it never solved my problem. 

Thanks to my OCS course, a bright light dawned on me. The reason why the TLS failed could be several. First of all, if you are running the sync service as a service on the server, the certificate must be in the trusted root of the computer, not the administrator (or other account which you are installing as). Second, if the service is set up to "run as" a separate user. It is a good idea to log on as that particular user, and import the certificate as that user. Quite simple when you think about it, but not always intuitive..... :P