Steps to reproduce:

1. Install zabbix_agent2-7.0.9-windows-amd64-openssl
2. Install zabbix_agent2_plugins-7.0.9-windows-amd64
3. Leave only mssql.conf, other plugins can be disabled by removing config files from C:\Program Files\Zabbix Agent 2\zabbix_agent2.d

Result:
PS C:\Program Files\Zabbix Agent 2> .\zabbix_agent2.exe -t agent.ping
zabbix_agent2 [11616]: ERROR: Cannot register plugins: failed to remove plugin socket, with path "\\\\.\\pipe
agent.plugin.sock": CreateFile \\.\pipe\agent.plugin.sock: All pipe instances are busy.

If I disable mssql plugin, agent starts working.

This is very strange behaviour , because it doesn't work out of the box.

Expected:
working agent