The error message "Failed to enable ASP.NET web extensions. Installation will not continue" appears when you install Symantec Mail Security for Microsoft Exchange (SMSMSE). The installer does not continue and SMSMSE is not installed.
There are various causes and solutions listed below.
1. Open IIS Manager. 2. Expand the Exchange server. 3. Click the Web Service Extensions folder. 4. In the list on the right make sure that ASP.NET v2.0.50727 is set to Allowed. 5. If ASP.NET is not listed please contact Microsoft for assistance.
Connecting to server ...Done HTTPODBC SSINC WEBDAV ASP.NET v2.0.50727 MSExchangeClienetAccess MSEXCHANGE SMSMSE BITSEXTS ASP
The list does not need to match exactly the example above, but this command should return a list of some extensions. The installer runs this command as a test to register the ASP.NET web extensions with IIS. If this script is not functioning properly, this command reveals that issue. If an error is returned when attempting to run this command, please contact Microsoft for further assistance troubleshooting why iisext.vbs is not functioning as expected.
If the iisext.vbs command shows the following error message:
Could not create an instance of the IIsScriptHelper object. Please, check if the Microsoft.IIsScriptHelper is registered.
Perform the following to register the IIsScriptHelper:
1. Open a windows command prompt. 2. CD to directory <windows>\system32. 3. Run the following command: regsvr32 IisScHlp.wsc.
On Windows 2008 R2, if the iisext.vbs command shows the following:
Connecting to server ...Done
This means ASP.NET v4.0 is the only version installed. Please download and install ASP.NET v3.5 as well.