Wylde had been doing double duty on the fest, opening the show with his own Black Label Society and then closing the show as Ozzy’s guitarist. He has been working non-stop for over a year recording and touring with Ozzy as well as recording his own album, 1919 Eternal, with his Black Label Society band.

Shows affected were those planned for Portugal, Switzerland, Denmark, Sweden, Finland and two in Russia.

The announcement comes on the heels of another canceled Ozzfest show. Ozzy and crew were set to play a two-night stand in Dublin but pulled the plug on the second show (May 26) when the rocker cited a throat infection.

However, Ozzy appeared to be clear of any throat problems when he performed for the Queen’s Jubilee celebration June 3. The Party At The Palace extravaganza featured artists from Brian Wilson to Ricky Martin performing during the event.

Said Ozzy of his invitation to rock Buckingham Palace: “I’m more surprised that anybody else that I’m here. My wife told me and I thought, ‘You’re pulling my leg.’ Heavy metal at the Palace? I’m not sure whether the Queen is a fan, but obviously she must be.”

North American Ozzfest dates are still on the books, with the traveling festival set to begin July 6 in Virginia.