ZLOrigin window has gone tiny and unusable

When I first installed ZLOrigin and ZClient, all worked fine. I've been playing my downloaded games via ZClient fine for the past few days, but I've gone back to use ZLOrigin - with nothing having changed since it worked after installation - and ZLOrigin will always briefly load a 'normal' size window but then a tiny window loads that cannot be resized and it has nothing inside.

Why could this happen, and how can I solve it without losing my installed games?

Thanks!

Screenshots:

How many zclients are running? It should be only one, also make sure its no av or defender block zlorigin, and clean the cacheDelOriginCache_.bat