Steps to reproduce:

Vcenter 6.7 with Zabbix default template to monitor it.

My Vmware zabbix_server.conf : **
{{StartVMwareCollectors=4
VMwareFrequency=60
VMwarePerfFrequency=60
VMwareCacheSize=256M
VMwareTimeout=30}}
Zabbix Server is installed on Centos 7.5.

You can find the error in the zabbix_server.log

Thanks