Caitlyn Jenner -- Instagram Blackout Over Hateful Comments

There was a Caitlyn Jenner blackout on ESPY day ... and the reason is all about hate.

We noticed late Wednesday morning if you hashtagged Caitlyn Jenner "most recent" would not come up. That means there was no way to see photos or texts using the hashtag.

The only photos you could see were from a few top posts ... all very nice and positive.

Here's what we found out. Instagram itself blocked its users ability to view "most recent" photos and texts, because there had been a flurry of really awful comments and uploads, including:

-- 'Until you grow a vagina and bleed, you will never be a woman'

-- 'F***ing Fa***t'

-- 'How is this THING rewarded anything'

There were so many negative comments and complaints about those comments, Instagram took swift action.

After Caitlyn took the stage, Instagram re-activated the hashtag and there was a flood of positive comments.

Nevertheless ... Caitlyn clearly has her work cut out for her.