classic .net app pool + iis 7.5 + compression modules

Question

I have windows 2008 r2 installed on my server, so iis 7.5 is. I am not able run any of the class.net applications on iis. one of the compression modules throws exception.

Detailed Error Information Module DynamicCompressionModule Notification SendResponse Handler StaticFile Error Code 0x8007007e Requested URL http://localhost:8081/a.html Physical Path C:\inetpub\TestWebSite\a.html Logon Method Anonymous Logon User Anonymous

i tried diferent logon methods, different sites even static html pages are not served. Error never changes.

sorry for poor english.

Answer 1

A quick bit of searching found this: http://forums.iis.net/t/1149768.aspx. Are you running a 64bit server? If so, is it possible you are (potentially inadvertently) mixing 32bit and 64bit code in the same application pool?

More information with slightly more detailed steps to resolve the problem found here: http://blogs.msdn.com/webtopics/archive/2010/03/08/troubleshooting-http-500-19-errors-in-iis-7.aspx (search down for error code 0x8007007e)

Error Message:

HTTP Error 500.19 - Internal Server Error The requested page cannot be accessed because the related configuration data for the page is invalid. Module DynamicCompressionModule Notification SendResponse Handler StaticFile Error Code 0x8007007e Requested URL http://localhost:80/ Physical Path C:\inetpub\wwwroot Logon Method Anonymous Logon User Anonymous

Reason:

Error Code 0x8007007e is:

ERROR_MOD_NOT_FOUND - The specified module could not be found.

This problem occurs because the ApplicationHost.config file or the Web.config file references a module that is invalid or that does not exist. To resolve this problem: In the ApplicationHost.config file or in the Web.config file, locate the module reference or the DLL reference that is invalid, and then fix the reference. To determine which module reference is incorrect, enable Failed Request Tracing, and then reproduce the problem.

For above specific error (mentioned in this example), DynamicCompressionModule module is causing the trouble. This is because of the XPress compression scheme module (suscomp.dll) which gets installed with WSUS. Since Compression schemes are defined globally and try to load in every application Pool, it will result in this error when 64bit version of suscomp.dll attempts to load in an application pool which is running in 32bit mode.

This module entry looks like:

Hence to get rid of this problem:

Ø Remove/Disable the XPress compression scheme from the configuration using the command below:

%windir%\system32\inetsrv\appcmd.exe set config -section:system.webServer/httpCompression /-[name='xpress']

OR

Ø Add an attribute of "precondition= "64bitness" for this module entry so that it loads only in 64bit application pools

Refer this blog for more details on Preconditions in IIS7

OR

Ø Use a 32bit version of suscomp.dll

Answer 2

many many thank daniel. %windir%\system32\inetsrv\appcmd.exe set config -section:system.webServer/httpCompression /-[name='xpress'] this command fixed my problem.