Just as Edward said in the comment, you must first configure your VSTS account have the corresponding access and permission in TFS server.
For example, if you have a domain account company/Ram Datla / Ram [email protected] and the user have add in your local TFS server.
For TFS you pay per user for team members who need to use Basic
features like Code or Agile Planning. Team members who have a Visual
Studio subscription are free to add because Basic features are
included in their subscription as a benefit.
If you haven't paid for this Ram [email protected] account. You could also be able to access TFS server , however just as a stakeholders, which provides access to a limited set of features. It's also free to add stakeholders to TFS.
If you have paid for the Ram [email protected] account with Basic level, then you could also use this account to also have Basic level(who need to use Basic features like Code or Agile Planning) in your local TFS server. Thus you don't have to pay this user again.
Q: Why should I pay via VSTS for my TFS users?
A: You get many benefits, for example:
- Paying via VSTS gives your users the flexibility to access both TFS and VSTS for the same price.
- You can pay monthly for users who need temporary access.
- You get all the purchasing capabilities that Azure offers, like payment via credit card, through a Cloud Solution Provider (CSP)
partner, through the Enterprise Agreement, and more.
Suggest you first go through below links with more detail explain of pricing:
Also take a look at the different Authentication of TFS and VSTS.