Ran install of Mid-tier 7.5 on a Windows 2008 machine;  chose IIS as webserver and Tomcat as JSP engine. Receiving either HTTP 404 or 500 errors when trying to reach the Mid-tier config page, or 500 errors.
AR/Mid-tier installer logs may show this severe error:
Severe error encountered:
SEVERE
com.bmc.install.product.arsuitekit.platforms.arsystemservers.midtier.MidTierTomcatUpdate
THROWABLE EVENT {Description=[Failed to execute updateWorkerPortNumber]}
Throwable=[java.io.FileNotFoundException: \conf\workers.properties.minimal (The system cannot find the path specified)java.io.FileInputStream.open(Native Method)java.io.FileInputStream.(Native Method)com.bmc.install.utility.io.FileHelper.readLines(FileHelper.java:708)com.bmc.install.utility.io.FileHelper.readLines(FileHelper.java:687)..
Windows Server 2008 Standard (32-bit and 64-bit) Service Pack 1
ProductBMC Remedy AR System Server (version 7.5.00)
EnvironmentDR: AR System Mid Tier;
SolutionHere are the steps taken at one site to ensure that the ISAPI redirector would install correctly (using the Midtier installer).

NOTE: If Mid-tier & Tomcat are already installed, please uninstall both via the Mid-tier uninstaller.  Please then download the latest patch of the AR/Mid-tier installer for step #3.
in IIS7, had to add new Roles to enable: ISAPI Filters and ISAPI extensions, CGI, IIS6 Metabase Compatibilityhad to set User Access Control for Windows in general to "disable" (OR log in as a local administrator account!)run Mid-tier installer, selecting IIS and Tomcatfrom the IIS Manager, open the 'ISAPI and CGI Restriction' iconadd path to the isapi_redirect.dllcheck the 'Allow extension path to execute box'if individual pages like login.jsp are getting sent back to the browser as a file-to-open, follow step #3 here:

http://www.mhsoftware.com/caldemo/manual/en/921.htm

If the home page login gives 404.11 from IIS (a double-escape security error):
followed the procedures here, http://support.microsoft.com/kb/942076
NOTE: If all steps are taken and the requests through the redirector receive a HTTP 503 response, a reboot of the Windows machine may be needed.

On 64-bit Windows with IIS7, the command-line procedures in the Installation Guide to allow the 32-bit .DLL still apply - however, two additional roles may need to be added to IIS before running those commands.
- IIS6 WMI Compatibility- IIS6 Scripting Tools
More information:
"1) Install the 6.0 compatibility role for IIS 7, and you should get the adsutil.vbs script; OR
2) Use the appcmd feature in IIS7 - see URLhttp://blogs.msdn.com/vijaysk/archive/2009/03/06/iis-7-tip-2-you-can-now-run-32-bit-and-64-bit-applications-on-the-same-server.aspx
With IIS 7.0 the Enable32bitAppOnWin64 key has been moved to the Application Pool level. So you can now set the bitness of a particular Application Pool:
appcmd set apppool /apppool.name:DefaultAppPool /enable32bitapponwin64:true
There is also a menu option for this ...see the URL. "

Ran install of Mid-tier 7.5 on a Windows 2008 machine;  chose IIS as webserver and Tomcat as JSP engine. Receiving either HTTP 404 or 500 errors when trying to reach the Mid-tier config page, or 500 errors.AR/Mid-tier installer logs may show this severe error:
SEVEREcom.bmc.install.product.arsuitekit.platforms.arsystemservers.midtier.MidTierTomcatUpdateTHROWABLE EVENT {Description=[Failed to execute updateWorkerPortNumber]}Throwable=[java.io.FileNotFoundException: \conf\workers.properties.minimal (The system cannot find the path specified)java.io.FileInputStream.open(Native Method)java.io.FileInputStream.(Native Method)com.bmc.install.utility.io.FileHelper.readLines(FileHelper.java:708)com.bmc.install.utility.io.FileHelper.readLines(FileHelper.java:687)..Windows Server 2008 Standard (32-bit and 64-bit) Service Pack 1ProductBMC Remedy AR System Server (version 7.5.00)EnvironmentDR: AR System Mid Tier;
Here are the steps taken at one site to ensure that the ISAPI redirector would install correctly (using the Midtier installer).
in IIS7, had to add new Roles to enable: ISAPI Filters and ISAPI extensions, CGI, IIS6 Metabase Compatibilityhad to set User Access Control for Windows in general to “disable” (OR log in as a local administrator account!)run Mid-tier installer, selecting IIS and Tomcatfrom the IIS Manager, open the ‘ISAPI and CGI Restriction’ iconadd path to the isapi_redirect.dllcheck the ‘Allow extension path to execute box’if individual pages like login.jsp are getting sent back to the browser as a file-to-open, follow step #3 here:http://www.mhsoftware.com/caldemo/manual/en/921.htmIf the home page login gives 404.11 from IIS (a double-escape security error):followed the procedures here, http://support.microsoft.com/kb/942076
On 64-bit Windows with IIS7, the command-line procedures in the Installation Guide to allow the 32-bit .DLL still apply – however, two additional roles may need to be added to IIS before running those commands.- IIS6 WMI Compatibility- IIS6 Scripting Tools
“1) Install the 6.0 compatibility role for IIS 7, and you should get the adsutil.vbs script; OR2) Use the appcmd feature in IIS7 – see URLhttp://blogs.msdn.com/vijaysk/archive/2009/03/06/iis-7-tip-2-you-can-now-run-32-bit-and-64-bit-applications-on-the-same-server.aspxWith IIS 7.0 the Enable32bitAppOnWin64 key has been moved to the Application Pool level. So you can now set the bitness of a particular Application Pool:appcmd set apppool /apppool.name:DefaultAppPool /enable32bitapponwin64:trueThere is also a menu option for this …see the URL. ”