Hi,
The http get request to vCenter Server to access the file on the datastore failed with HTTP 500.
Details should be available in vpxd logs of vCenter Server.
You can also try to access via web browser some file on the same datastore:
https://vcenterserver/folder/path1/filename?dcPath=DatacenterName&dsName=datastoreName
For example: https://10.23.68.94/folder/testvm03/testvm03.vmx?dcPath=DC1&dsName=datastore1-5
Regards,
Martin