Upload file to datastore, certificate error.

To fix this

1. Browse to VirtualCenter
2. Down at the right bottom on page press Download trusted root CA
3. Unpack the zip file
4. Open Certmgr.msc
5. Go to Trusted Root Certification Authorities
6. Rightclick on Certificates and All Taska/ Import
7. Import the certificates that you unzipped before
8. Restart Browser

Done!