PNG export issue

Been dealing with this issue for months, awaiting for various updates to resolve, and no luck. Cannot find anything online about it, so now I am here. 

When exporting a PNG file from Illustrator, the vast majority of time the files are corrupted. They don't preview in finder, you get a "end of file" warning when trying to open in Photoshop, etc. This issue is happening in a coporate environment accross various computers and geographical areas. We use a cloud file service called Egnyte to store our files on, and this is where we save the files, not sure it's an issue associated with that. We have tried saving locally to desktops, then transferring the files to Egnyte, and find the same problem. Sometimes the files look ok to the person who exported them, but then appear "corrupted" to other users.

We have .ai files that are 100+ artboards long that we have tried, and completley different files where there's only 1 or 2 artboards, but the same issue occurs. The odd one seems to get through, but 90%+ of others end up corrupted.

Any light that can be shed on this issue would be appreciated.