IIS Service Unavailable and W3SVC-WP 2274 event log error

[Ovid]

I'm running IIS6 and Exchange 2007. Everything was working file until 0810
this morning. When a user tries to open the default web site, they get a msg
Service Unavailble. In the application log, I get the following:
ISAPI Filter
'C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\\aspnet_filter.dll' could not
be loaded due to a configuration problem. The current configuration only
supports loading images built for a AMD64 processor architecture. The data
field contains the error number. To learn more about this issue, including
how to troubleshooting this kind of processor architecture mismatch error,
see http://go.microsoft.com/fwlink/?LinkId=29349.

I think the problem is a conflict with versions of .NET 2. If I look at
Add/Remove Programs, I'm seeing version 2.1.21022 (SP1). But if I look in IIS
under WebService Extensions, it's shoing ASP.NET v2.0.50727 (allowed). I'm
not sure how to fix this. I tried via this link
http://support.microsoft.com/kb/894435 and it appeared to work (v.2.0 was in
that path), but nothing changed (probably due to the 2.0 vs. 2.1 issue).

Don't know how to fix this. Thanks.

[David Wang]

You installed something that changed 64bit IIS to load up the 32bit
aspnet_filter.dll. I assume IIS is 64bit because Exchange 2007 is
64bit.

What needs to happen is that IIS needs to load the 64bit
aspnet_filter.dll under C:\WINDOWS\Microsoft.NET
\Framework64\v2.0.50727\aspnet_filter.dll . This is corrected with the
appropriate version of aspnet_regiis.exe under the Framework64
directory.

FYI: This issue:
- Has nothing to do with imagined "conflict" between versions. Add/
Remove Programs and Web Service Extensions have no relation
- Web Service Extensions affect ISAPI Extensions, not ISAPI Filters,
so it is not related
- The KB you mentioned is for switching bitness, which you cannot do
because Exchange 2007 (OWA) requires 64bit IIS

I suspect you installed 32bit .Net Framework SP1 instead of 64bit. Or
you ran something that is 32bit and assumed 32bit ASP.Net
configuration instead of the correct configuration. Unfortunately, you
will have to unwind all the little 32bit legacy compatibility issues
yourself because 64bit Windows allows execution of 32bit programs.

This problem is particularly acute for IIS because its extension
mechanism is via DLLs, and since you cannot mix bitness between DLL
and the EXE process that loads it, it is insanely easy to mismatch it
on IIS6 and get into the bad state you are in if you run legacy or
install 32bit Web Applications on IIS6 running on 64bit Windows. But,
that's the price one must pay for dramatic compatibility such as 32bit
applications on 64bit OS.


//David
http://w3-4u.blogspot.com
http://blogs.msdn.com/David.Wang
//

Post by Ovid
I'm running IIS6 and Exchange 2007. Everything was working file until 0810
this morning. When a user tries to open the default web site, they get a msg
ISAPI Filter
'C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\\aspnet_filter.dll' could not
be loaded due to a configuration problem. The current configuration only
supports loading images built for a AMD64 processor architecture. The data
field contains the error number. To learn more about this issue, including
how to troubleshooting this kind of processor architecture mismatch error,
seehttp://go.microsoft.com/fwlink/?LinkId=29349.
I think the problem is a conflict with versions of .NET 2. If I look at
Add/Remove Programs, I'm seeing version 2.1.21022 (SP1). But if I look in IIS
under WebService Extensions, it's shoing ASP.NET v2.0.50727 (allowed). I'm
not sure how to fix this. I tried via this linkhttp://support.microsoft.com/kb/894435and it appeared to work (v.2.0 was in
that path), but nothing changed (probably due to the 2.0 vs. 2.1 issue).
Don't know how to fix this. Thanks.