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I want to host an ASP.NET 4.0 web application in IIS 6 on Windows 2003 R2 SP2 x64.

Is this even possible? I have the following under C:\WINDOWS\\Framework

  • 1.0.3705
  • 1.1.4322
  • 2.0.50727
  • 3.0
  • 3.5
  • 4.0.30319

and in C:\WINDOWS\\Framework64 the same except 1.0 and 1.1.

IIS 6 runs in 32 bit mode but there is no ASP.NET tab in the properties screen of the website. So I can't switch frameworks and don't know what frameworks runs in what application pool.

EDIT have tried what GregD suggested. That gave me back the tab in IIS so that I could set the proper framework for the website, but it gave me the following in the eventlog when I tried to start the application pool:

Could not load all ISAPI filters for site/service. Therefore startup aborted.

After a quick googling, I found this:

Which kind of puts me in a circle. Enabling and removing the 64 bit setting in the metabase.xml file.

Because aspnet_regiis -i told me that it couldn't work because IIS was in a 64-bit setting.

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up vote 1 down vote accepted

You can do it.

On your web service extensions folder (in IIS Manager) are your extensions enabled for the different versions?

Edited to add: To get your tab back try this:

1) Stop the IIS Admin service (and any services that depend on it)

2) Open C:\WINDOWS\system32\inetsrv\MetaBase.xml in notepad or your favorite XML Editor. DELETE the line that reads ‘Enable32BitAppOnWin64=”TRUE”’

3) Restart IIS

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yes it's all enabled. but i can't switch frameworks, the tab is not there – JP Hellemons Jul 30 '10 at 13:48
Is this running on VMWare by chance? – GregD Jul 30 '10 at 13:58
Hello GregD, it's not running on VMWare, just a normal win 2003 x64 install. but i cannot switch .net frameworks in iis. – JP Hellemons Aug 2 '10 at 7:23
Editing the MetaBase.xml file worked perfectly for me. Thanks – AndyMcKenna Aug 10 '10 at 6:58
It gave me my option back to select 4 but then got this in the eventlog: Description: Could not load all ISAPI filters for site/service. Therefore startup aborted. will take a closer look tomorrow :) thanks! – JP Hellemons Aug 10 '10 at 15:06

It works now. It seems that I can't have the option in IIS to switch frameworks.

I did:

C:\WINDOWS\\Framework\v4.0.30319>cscript c:\inetpub\adminscripts\adsutil.vbs SET /w3svc/AppPools/Enable32BitAppOnWin64 True

and then

C:\WINDOWS\\Framework\v4.0.30319>aspnet_regiis.exe -i -enable

and it worked! As I said, no ASP.NET tab is visible in IIS, but it works!

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