1. Add role – IIS
2. Add Feature – IIS -> CGI
3. Download WebPI
4. Install WebPI with php 5.6
5. Restart
for hmailserver
6. In “Default Web Site” , click php manager
7. Scroll down to PHP Extensions, enable “php_com_dotnet.dll”
8. dcomcfg.exe
https://www.hmailserver.com/documentation/latest/?page=howto_dcom_permissions
9. permit hmailserver.dll to IIS_IUSRS with “local launch” and “local Activation”
https://www.hmailserver.com/forum/viewtopic.php?t=14527