Client Access Licence (CAL) User – Remote Desktop Windows Server 2025

The RDS User CAL for Windows Server 2025 authorises one designated person to open Remote Desktop sessions on your server, from an unlimited number of terminals. It is a right of access, not software: no installation on the client side, the key is recorded on the licence server. It is the appropriate licence for organisations that centralise their applications and whose staff work from several machines.

What a CAL does — and does not — cover

• It never replaces the server licence. Windows Server 2025 is licensed per core; access is licensed on top, per CAL. Both are required.
• RDS CALs add to Windows Server CALs. Each Remote Desktop session uses a Windows Server CAL and an RDS CAL. The RDS CAL is not a substitute: it is a complement. This is by far the most widespread confusion.
• It is by name. A User CAL is assigned to a person, not lent according to the connections.
• It is perpetual for its generation. A 2025 CAL covers a 2025 server or earlier, which also makes it usable with an older fleet.

User or Device

Take User CALs when your workforce connect from several devices — remote working, personal equipment, mobility. Take Device CALs when several people take turns on the same workstations. The calculation is always the same: license the smaller of the two headcounts, devices or users.

Windows Server 2025 on the Remote Desktop side

The 2025 generation modernises the display protocol (better handling of multi-monitor and low-bandwidth sessions), strengthens authentication and fits into the system's Secured-core approach. Its extended support runs until October 2034: it is today the most durable foundation in the catalogue.

Activation

The key reaches you by e-mail within 24 hours at most. On the server: Remote Desktop Services licence manager › activate the licence server › install the licence pack with the key received › set the mode to “Per user”.

Buy an RDS CAL Windows Server 2025

Odin Key is operated by CHKEY OÜ, an Estonian company. Official invoice, support by e-mail. Key sent by e-mail within 24h after payment.