Renewal or Reinstatement for plesk 7.6 windows?

[webjobs]

Good morning.

We are a websites agency and we mount Plesk 7.6 for windows, but know its expired, and there is a message who sais: You are currently operating within the grace period of your product license. To update your product license, select the Retrieve Keys option on the License Management page.

In the Parallels website I went to this page: http://www.parallels.com/en/buyonline/support/plesk/win/

We have the Plesk Unlimetd domains license but we dont understand the difference between: Renewal and Reinstatement.

Could you please let me know the difference between the two options and which one I have to buy for to be sure that everything will work like now?

Thank you

Best regards

Lorenzo Erba