'ASP 0201' Invalid Default Script Language
This is a pretty common ASP error that could due to number of reasons; before we go into various ways to fix this error, let’s take a look at the error itself. So what’s the complete error message? Well, I got the following when simulating one of the possible cause of this. Typically, you will see this:
Active Server Pages error 'ASP 0201'
Invalid Default Script Language
The default script language specified for this application is invalid.
Or similar error message as highlighted in this KB - ASP0201: Invalid Default Script Language. As indicated in the article, the error is caused by non-supported scripting languages that IIS is unable to recognize. Now how to fix this? Try the following:
1) Make sure proper scripting language is defined in IIS. As per the above article, make sure the Default ASP Language is set to VBScript (by default), or JScript if you preferred Java Scripting.
2) Take note that your code will override the first setup if you have <% Language=”language” %> defined at the beginning of your script. So, double checks to ensure you don’t have spelling or typo error. It should be <% Language=”VBScript” %>
3) From time to time, this may due to incomplete DLL registration for those scripting engine and to get the scripting engine up to date, please get the latest scripting engine here. At the time of this writing, the latest version is 5.6.
4) Now, I have seen issue when installing the Scripting engine, e.g. unable to register certain DLLs, etc. What you can try next is to register the following DLLs:
regsvr32 %windir%\system32\VBscript.dll
regsvr32 %windir%\system32\JScript.dll
regsvr32 %windir%\system32\Inetsrv\Asp.dll
5) Moving on, if you reach this step, it is likely due to permission issue. E.g. iusr_computername account for anonymous access does not has READ permission over the related DLLs, you then try grant NTFS read permission to the DLLs in step 4 for your request account.
6) Next, following step 5 – if you still facing the same problem, you could take another step to ensure that all relevant permissions are in place, refer the following KBs:
IIS 4 - Required NTFS permissions and user rights for IIS 4.0
IIS 5 - How to set required NTFS permissions and user rights for an IIS 5.0 Web server
IIS 6 - Default permissions and user rights for IIS 6.0
7) Typically, if you have followed all the previous steps you should no longer see the same error message. Just in case, you missed some of the configurations in earlier steps, you can then temporary make the iusr_computername or your defined request user account to the local administrators group. Take note, this is just for troubleshooting purpose! You should NOT grant the default anonymous account with local administrative rights, and make sure after the troubleshooting you remove the account for the administrators group.
The idea behind this is to check if adding the user to this administrators group fixes the error, if yes, it is confirmed that there are yet permission issues that not being addressed or overlooked in previous steps. After removing the account from the administrators group, you can then get Filemon and Regmon from sysinternals.com to trace the permission issue.