I wish I could help you, only that I have the exact same problem. the only way I can play is when I click on install again.
same for me but i can play the game with out the launcher
to do that go to
C:\Program Files (x86)\Zenimax Online\The Elder Scrolls Online EU\game\client
then press: eso
it wil launche the game without the laucher but you wil have no updates thats the bad part of it