Maintenance for the week of March 16:
• PC/Mac: No maintenance – March 16
• ESO Store and Account System for maintenance – March 18, 6:00AM EDT (10:00 UTC) - 4:00PM EDT (20:00 UTC)
That's the case since the IC update.. I heard it lot from others, and during the last ~2 weeks, I have a character questing there myself. Everything is slowed down as hell, or it doesn't work at all.