Take your pick, they all fit the situation: alarming, worrying, daunting, perturbing, niggling, nagging, bothersome, troublesome, unsettling, nerve-racking; distressing, disquieting, upsetting, traumatic, problematic; informalscary, hairy
I tried to get on a few times and same thing----no site to be found. I figured it was something very unusual because I frequent several other sites that are of interest to me and every once in a while they go down for one reason or another. Glad to see all is well.