I attempted to install SP1 on one of the two CAS/HUB servers in my CAS Array. I put the rollup of SP1 in the updates folder and received this error after the RTM was uninstalled and services stopped and disabled: [11/30/2010 04:36:10.0744] [1] ProductCode is '4934d1ea-be46-48b1-8847-f1af20e892c1'. [11/30/2010 04:36:10.0744] [1] PackagePath was set to '\\server\software$\EXCH201064SP1\exchangeserver.msi'; changing to full path '\server\software$\EXCH201064SP1\exchangeserver.msi'. [11/30/2010 04:36:10.0775] [1] ProductCode is '4934d1ea-be46-48b1-8847-f1af20e892c1'. [11/30/2010 04:36:10.0791] [1] Installing MSI package '\\server\software$\EXCH201064SP1\exchangeserver.msi'. [11/30/2010 04:36:10.0791] [1] Patch file '\\server\software$\EXCH201064SP1\Updates\Exchange2010-KB2407028-x64-en.msp' was found in the patch directory. [11/30/2010 04:36:10.0822] [1] Found a valid order for the available patches. [11/30/2010 04:36:10.0838] [1] Patch '\\server\software$\EXCH201064SP1\Updates\Exchange2010-KB2407028-x64-en.msp' has order '0'. The status code returned was '0'. [11/30/2010 04:36:10.0838] [1] Patch '\\server\software$\EXCH201064SP1\Updates\Exchange2010-KB2407028-x64-en.msp' is valid for the current .msi package. The patch order is '0'. [11/30/2010 04:36:10.0838] [1] The patch attribute will be set to '\\server\software$\EXCH201064SP1\Updates\Exchange2010-KB2407028-x64-en.msp;' for the .msi package. [11/30/2010 04:36:10.0838] [1] Installing a new product. Package: \\server\software$\EXCH201064SP1\exchangeserver.msi. Property values: PATCH="\\server\software$\EXCH201064SP1\Updates\Exchange2010-KB2407028-x64-en.msp;" DISABLEERRORREPORTING=1 PRODUCTLANGUAGELCID=1033 DEFAULTLANGUAGENAME=ENU DEFAULTLANGUAGELCID=1033 INSTALLCOMMENT="Installed language for this product: English (United States)" REBOOT=ReallySuppress TARGETDIR="C:\Program Files\Microsoft\Exchange Server\V14" ADDLOCAL=Bridgehead,ClientAccess,AdminTools,AdminToolsNonGateway [11/30/2010 04:39:25.0515] [1] [ERROR] Unexpected Error [11/30/2010 04:39:25.0515] [1] [ERROR] Installing product \\server\software$\EXCH201064SP1\exchangeserver.msi failed. Fatal error during installation. Error code is 1603. [11/30/2010 04:39:25.0515] [1] [ERROR] Fatal error during installation [11/30/2010 04:39:25.0546] [1] Ending processing install-msipackage [11/30/2010 04:41:10.0336] [0] End of Setup I got the RTM reinstalled back to where the HUB is installed but the CAS role is failing with: Error: The following error was generated when "$error.Clear(); set-ClientAccessServer -Identity $RoleFqdnOrName" was run: "Field not found: 'Microsoft.Exchange.Data.Directory.Management.AlternateServiceAccountCredential.UserNameComparer'.". Field not found: 'Microsoft.Exchange.Data.Directory.Management.AlternateServiceAccountCredential.UserNameComparer'. I only found one mention of this when searching the web. Any ideas? Thanks, Mike

I got MS on the phone and just ended up getting RTM back up and running. I think the initial isue had to do with putting the SP1 rollup 1 in the updates folder in the SP1 folder structure. I will install SP1 again when I can schedule downtime and update this thread. Believe you me I will not be putting that rollup1 in the updates folder next time ;-)

Just to validate your thinking, you are correct, you cannot slipstream an update rollup as part of an SP installation. Update rollup slipstreams are only supported for new installations. See link: http://technet.microsoft.com/en-us/library/ff637981.aspx "Slipstream Update Rollup Installations Exchange 2010 doesn't support the slipstream installation of an update rollup during the installation of a service pack. The Exchange installation folder includes an Updates folder. The Updates folder supports a new installation of Exchange. When you perform a new Exchange installation, you can copy an update rollup to the Updates folder. In this scenario, the update rollup package is applied during the installation of Exchange. To perform a supported new installation, follow these example steps: Copy the Exchange 2010 RTM files to a local directory on the server or to a network share. Place the appropriate update rollup package in the Updates subdirectory. Install Exchange. The update rollup is automatically applied during the installation of Exchange. The Updates folder isn't supported for use during a service pack installation. Therefore, you can't include (that is, slipstream) an update rollup along with the installation of a service pack. The slipstream installation of an update rollup during a service pack installing hasn't been tested. Therefore, you may experience unintended results. To perform a supported upgrade installation, follow these example steps: Install Exchange 2010 Service Pack 1 (SP1) on a computer that is running Exchange 2010 RTM together with Exchange 2010 Update Rollup 1. Install Exchange 2010 SP1 Update Rollup 2." Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

Do you have the link like the one above that outlines the procedure for installing SP1 on a CAS Array? Thanks