I had premium packs installed on my Tyros 4 when I purchased it secondhand, but I had to send it away for repairs, in the process some of the content of the premium packs got erased.
Unfortunately the person whom I purchased it from had passed away and had no means of getting information to retrieve the packs.
The other day I contacted Yamaha Customer Support explaining my position, they initially asked if I had any email or name details, I couldn’t locate any.
Thankfully though the kind people at Yamaha managed to transfer the majority of packs to my account so I can now reinstall them.
Thanks Yamaha.
