Now, let me start by saying that I can install Exchange 2003 on a Server 2003 box without problems. I have a AD machine at home that I use as my everything server. I went ahead and did a new install of Server 2008 and get errors while trying to install Exchange 2003 on it. I installed IIS but noticed while going through the Exchange Deployment checklist that I couldn't find SMTP and NNTP services to install via Server 2008? So Question #1 - Where has that stuff been moved to? I'll also note that I've been researching the below errors on google for days and have tried several of the DNS related KB articles (i.e, allow dynamic updates, changing adsiedit settings, etc) & none of that worked.Here's the first error pop-up error I get when I get to the /forestprep step of the Exchange install. It happens uring the "configuring registry entries for microsoft windows active directory schema update" :The specified module could not be found.Facility: Win32ID no: c007007eMicrosoft Active Directory - Exchange ExtensionI now click OK, hit close program and this messege appears:Setup failed while installing sub-component Microsoft WindowsActive Directory schema update with error code 0xC103798A(please consult the installation logs for a detailed description). Youmay cancel the installation or try the failed setup again.I'll hit cancel and check the logs, here is the log where I believe the error starts:[10:16:12] ++++ Starting interpreter on file d:\exchange server 2003\i386\setup\i386\exchange\schema.ins ++++ -- ID:31258 --[10:16:12] Interpreting line <CreateProcess:\exchange server 2003\i386\setup\i386\exchange\bin;regsvr32.exe /i /n /s maildsmx.dll;4294967295> -- ID:31259 --[10:16:12] Process created ... waiting (-1)[10:17:59] Process has exited with 0xc0000005[10:17:59] The command regsvr32.exe /i /n /s maildsmx.dllfailed, returning error code -1073741819 (Access is denied.). -- ID:31136 -- ScCreateProcess (f:\titanium\admin\src\libs\exsetup\hiddenw1.cxx:1821) Error code 0XC103798A (31114): An internal component has failed.[10:17:59] CInsParser:cProcessLine (f:\titanium\admin\src\libs\exsetup\hiddenw1.cxx:1225) Error code 0XC103798A (31114): An internal component has failed.[10:17:59] Processing file 'd:\exchange server 2003\i386\setup\i386\exchange\schema.ins', at or near line 8 (CreateProcess:\exchange server 2003\i386\setup\i386\exchange\bin;regsvr32.exe /i /n /s maildsmx.dll;4294967295) -- ID:31111 -- CInsParser:cProcessLine (f:\titanium\admin\src\libs\exsetup\hiddenw1.cxx:492) Error code 0XC103798A (31114): An internal component has failed.[10:17:59] Registry file name: 'd:\exchange server 2003\i386\setup\i386\exchange\schema.ins' CRegistryManager:cProcessFile (f:\titanium\admin\src\udog\setupbase\tools\regmgr.cxx:125) Error code 0XC103798A (31114): An internal component has failed.[10:17:59] Filename = 'd:\exchange server 2003\i386\setup\i386\exchange\schema' CBaseAtom:cAddRegistryKeys (f:\titanium\admin\src\udog\setupbase\basecomp\baseatom.cxx:1408) Error code 0XC103798A (31114): An internal component has failed.[10:17:59] CAtomSchema:cAddRegistryKeys (f:\titanium\admin\src\udog\exsetdata\components\root\a_schema.cxx:318) Error code 0XC103798A (31114): An internal component has failed.[10:17:59] Leaving CAtomSchema:cAddRegistryKeys[10:17:59] CAtomSchema:cAdd (f:\titanium\admin\src\udog\exsetdata\components\root\a_schema.cxx:150) Error code 0XC103798A (31114): An internal component has failed.[10:17:59] Leaving CAtomSchema:cAdd[10:17:59] mode = 'ForestPrep' (61965) CBaseAtom:cSetup (f:\titanium\admin\src\udog\setupbase\basecomp\baseatom.cxx:842) Error code 0XC103798A (31114): An internal component has failed.Any help is appreciated!

Exchange 2003 can NOT be installed on Windows 2008, take a look here Exchange Server and Windows Server 2008

Amit Tank wrote: Exchange 2003 can NOT be installed on Windows 2008, take a look here Exchange Server and Windows Server 2008 You sure that's the problem? This is confusing, cannot be installed but will be supported... what!?! My 2008 server is a domain controller."Exchange 2003 cannot be installed on Windows Server 2008, but will be supported with Windows Server 2008 domain controllers."

That means Exchange 2003 can not be installed on Windows 2008 operating system but If you have Windows 2008 DC in your environment then Exchange 2003 (which is installed on Windows 2003 operating system) can use Windows 2008 DC for Active Directory communication.

Ok, so answer me this then. I have a 32-bit system... will exchange 2007 install on it (non-supported of course) or would I just be better off re-installing 2003 server?

Yep, Exchange 2007 SP1 is the only versionthat can beinstalled on Windows Server 2008 so I feel it shouldn't give you any problem. Exchange Server and Windows Server 2008, Part II