Hello,
Yes, you would still need Client Access Licenses (CALs) for each user or device that accesses the server, even if you are only using Active Directory and not utilizing any other Microsoft server features or shares. CALs are required for using Microsoft server software, and Active Directory is included under this requirement.
Since you have 50 users, you would need either 50 User CALs (if each user accesses the server from multiple devices) or Device CALs (if multiple users share the same device). You need to determine which type of CAL is more cost-effective for your particular situation.
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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