For anyone who is unable to access their ideabooks (mine were unavailable to me from the Houzz home page for four months!), just go to your icon pages and DELETE Houzz. Then re-download Houzz from the cloud (I went to my apple app-store site to do that). Problem solved. I can access my ideabooks again. I have no idea what the problem was, but that solved the issue. I was prepared to delete my account , but that was not necessary.