Hello Matova,
Thanks very much for upgrading to v7.
Due to the different licensing systems between v4 and v5+ (HASP vs. iLok) you need to download and install v5+ compatible versions of any encrypted sample sets that you might have, including any from Milan Digital Audio. The download links for MDA's (and Paramount's) can be found are here:
viewtopic.php?f=10&t=17988
(If you have from other sample set creators, please contact them for their download links if needed.)
Please also note that before you will be able to install or load any of your licensed sample sets you will need to have migrated your licences from the v4 Hauptwerk USB Key dongle to the iLok system. For that, you need to have purchased this item:
https://www.hauptwerk.com/hauptwerk-license-migration/
I believe you will then be emailed the necessary instructions for migrating the licences, but if not, or if in doubt, let us know.