The question we get most often after someone sets up Tally or an office application on a Windows VPS is why the third person cannot log in. The answer is licensing, and once explained, RDS CALs are simple.
Two sessions are free, by design
Windows Server allows two simultaneous Remote Desktop connections for administrators without any additional licence. Microsoft intends these for managing the server, not for users working on it. A third connection either fails or disconnects one of the first two.
What RDS licences are
To let more people work on the same server at once, Windows needs the Remote Desktop Services role, specifically the RD Session Host, and a licence for each user or device that connects. On an owned server these are Client Access Licences, RDS CALs, bought once. On a rented server they are licensed by the host through Microsoft's programme for service providers, as a monthly per-user charge. The effect is the same: one licence per person who logs in.
Per user or per device
Per user covers one named person on any number of devices: office PC, laptop, phone. Per device covers one machine used by any number of people, such as a shared front-desk PC. For most offices, per user is the right choice. On rented servers, per-user licensing is the norm.
How many RDS CALs you need
Count the people who will ever log in, not how many will be on at once. A practice with five staff who use Tally at different times of day still needs five per-user licences. Two of them can be covered by the built-in administrative sessions only if those two are genuinely administering the server; for ordinary users, license everyone.
What happens without them
Windows offers a 120-day grace period after the RDS role is installed. When it ends, connections beyond the two administrative sessions are refused. This is why a setup that "worked fine for months" suddenly stops on a Monday.
How we set it up
When you tell us the number of users, we install the RD Session Host role, configure the licensing server, and add the per-user licences to your monthly bill. Each person gets their own Windows login. The Windows Server licence itself is already included in our plan price; RDS licences are the only addition, and only from the third user.
Sizing the server for many users
Roughly 1 GB of RAM per concurrent user plus 3 GB for Windows and the application. Eight GB for up to five users on Tally or office software, sixteen for ten to fifteen. Heavier applications need more; ask us with your user count and application.
Questions we get asked
Can I avoid RDS licences with a registry change? There are guides online that do. They breach the Windows licence and the session limit comes back with updates. Do not run a business server that way.
Do I need RDS for two users? If both are administrators, no. For two ordinary users working all day, license them properly.
Can I bring my own RDS CALs? On a rented server, usually not; licensing must come through the provider's agreement. Ask us about your case.
Does Tally need RDS? Tally Gold allows many users; Windows still needs RDS licences for more than two to be logged in at once.
Does a Linux server have this limit? No, but Tally and most Windows business software do not run on Linux.
