Which sync.blue® IPs can I enable in my firewall? Ing. Oliver Baltz October 17, 2022 14:50 Updated Visible to the outside is the following IP: 184.108.40.206 Use this source IP to allow access to your apps. Related articles How secure is synchronizing my contacts with sync.blue®? Which apps is sync.blue® compatible with? Where can I download an AVV (agreement on commissioned data processing)? Why did I receive an invoice? What does "Couldn't connect to..." mean? Comments 0 comments Please sign in to leave a comment.