Hi there,
So you are asking whether CAL is required to use a File server?
If so Yes, the workstations in your organization are networked, you likely depend on network server software to perform certain functions, such as file and print sharing. To access this server software legally, a Client Access License (CAL) may be required.
https://www.microsoft.com/en-us/licensing/product-licensing/client-access-license
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