Xfdumanifest.xml import error

Good day

When I try to import the xfdumanifest.xml file i receive and error message. I do not know if it is a download problem or the softwtare problem. I am trying to use Sentinel 3 OLCI data in SNAP 5.0. I need help on howfix the problem with the file.

can you tell me which file you are using? The complete directory name would help. or the name of the zip file.
Also it would be good to know from where you got the file. From SciHub, from Eumetsat?
Have you already tried to download it again?