Today, I was asked by HaoSiaoKing aka Kwan for this case and I am now sharing the solution.
Scenario: When create a subdomain from HELM3 but all of the script mapping is not created automatically. I tried to use a alternative way to make it working as solution below.
1. The workaround I am using is to replace all of the script mapping back to the subdomain where is it not created by the subdomain.
2. Open IIS6, you shall see the hostname and right click then select the properties.
3. Check the checkbox of “Enable Direct Metabase Edit” and press OK.
4. Go to the directory of “C:\WINDOWS\system32\inetsrv”.
5. Backup the file named MetaBase.xml.
6. Open the file with notepad.
7. Find the domain name from the MetaBase.xml file.
8. Copy the line as below.
9. Find the subdomain.
10. Paste the copied line and replace the ScriptMaps.
11. Restart IIS.