When copying the certificate over to the host with pcsp for some reason they file is always malformed when going over. If you do a cat rui.crt you will see no issue, but if you do a vi rui.crt then you will see that each and every line has a ^M at the end of it – this is because the file is a dos format file.

I finally found a to remove them – and it was not easy to find.
Both tr and dos2unix are not available on ESXi
sed 's/'"$(printf '\015')"'$//
s/'"$(printf '\032')"'$//' rui.crt > rui.new
That produces a clean file.

Phew – now I can rest easy…
Update:
Thanks to the comment received from JR below it is even easier
sed 's/.$//' < rui.crt > rui.new