problem migrating from starter to business pack

-- url of the page with the problem -- : www.graphicstyle.dk
-- HikaShop version -- : 2.6.0
-- Joomla version -- : 3.4.5
-- PHP version -- : 5.6
-- Browser(s) name and version -- : safari 9.0
-- Error-message(debug-mod must be tuned on) -- : Warning
JFolder::create: Infinite loop detected.

Warning: Failed to move file!

Error
Unable to read archive

Unable to find install package

Hi

I have a big problem upgrading from the fre starter pack to the business pack that I just purchased.
As far as I can see, I should be able to just upload the business pack file onto of my starter, but I get error messages.
Do I need some kind of a update file instead of the full version? What do I need to do to get this update to work?
Kind regards
Birgitte Skyum