Hello,
i'm running the VCSA since a couple of months and tried to update it to 5.0 Update 1a (http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2031331). After 14 hours the Update was running, middle in database-upgrade, nothing happened anymore, that's why i've rebooted the Vcenter appliance. It never came up again 
Well, then i've made a restore through Veeam and finally the Vcenter appliance is running again, with the old 5.0.03324 Build 472350.
Now i would to try to Update the Appliance to 5.0.0.5239 Build 759855 again, but the Update failed before it really starts
What can i do?
Error: Failed to install updates (Error while running installation tests and post-install scripts
Version - 5.0.0.3324 Build 472350
Description - VMware vCenter Server Appliance
Update to version 5.0.0
08/08/2012 05:48:35 18860 main:UA_CLI.cpp:187 (updatecli) [INFO] Starting Install
08/08/2012 05:48:35 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Starting Install
08/08/2012 05:48:35 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Running pre-install scripts
08/08/2012 05:48:35 18860 executeFile:UA_CLI.cpp:86 (updatecli) [INFO] Running /opt/vmware/var/lib/vami/update/data/job/38/pre_install '5.0.0.3324' '5.0.0.5239'
Installing update from version 5.0.0.3324 to version 5.0.0.5239
Stopping VMware vSphere Profile-Driven Storage Service...
Stopped VMware vSphere Profile-Driven Storage Service.
Stopping VMware Inventory Service...
Stopped VMware Inventory Service.
Stopping tomcat: success
Stopping vmware-vpxd: success
Shutting down ldap-server..done
VMware vSphere Client is not running.
08/08/2012 05:48:50 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Done pre-install scripts
08/08/2012 05:48:50 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Running installation tests
08/08/2012 05:48:50 18860 executeFile:UA_CLI.cpp:86 (updatecli) [INFO] Running /opt/vmware/var/lib/vami/update/data/job/38/test_command
warning: /opt/vmware/var/lib/vami/update/data/package-pool/package-pool/vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64.rpm: Header V3 RSA/SHA1 signature: NOKEY, key ID 66fd4949
Preparing packages for installation...
file /etc/vmware-tools/poweroff-vm-default from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
file /etc/vmware-tools/poweron-vm-default from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
file /etc/vmware-tools/resume-vm-default from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
file /etc/vmware-tools/suspend-vm-default from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
file /etc/vmware-tools/tools.conf from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
file /sbin/mount.vmhgfs from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
file /usr/bin/vmware-hgfsclient from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
file /usr/bin/vmware-xferlogs from install of vmware-open-vm-tools-common-8.3.2-292861.sles11sp1.x86_64 conflicts with file from package open-vm-tools-2008.09.03-5.45.x86_64
08/08/2012 05:48:55 18860 executeFile:UA_CLI.cpp:92 (updatecli) [ERROR] Failed with exit code 65024
08/08/2012 05:48:55 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Running post-install scripts
08/08/2012 05:48:55 18860 executeFile:UA_CLI.cpp:86 (updatecli) [INFO] Running /opt/vmware/var/lib/vami/update/data/job/38/post_install '5.0.0.3324' '5.0.0.5239' 2
Failed with status of 2 while installing version 5.0.0.5239
VM version is still 5.0.0.3324
08/08/2012 05:48:55 18860 executeFile:UA_CLI.cpp:92 (updatecli) [ERROR] Failed with exit code 256
08/08/2012 05:48:55 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Running VMware tools reconfiguration
08/08/2012 05:48:55 18860 executeFile:UA_CLI.cpp:86 (updatecli) [INFO] Running /opt/vmware/share/vami/vami_reconfigure_tools
Configuring VAMI VMware tools service wrapper.
vmware-toolbox-cmd is /usr/bin/vmware-toolbox-cmd
08/08/2012 05:48:55 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Done VMware tools reconfiguration
08/08/2012 05:48:55 18860 updateStatus:UA_CLI.cpp:45 (updatecli) [INFO] Update status: Error while running installation tests and post-install scripts
08/08/2012 05:48:55 18860 main:UA_CLI.cpp:223 (updatecli) [ERROR] Failure: updatecli exiting abnormally
08/08/2012 05:48:55 18860 main:UA_CLI.cpp:225 (updatecli) [INFO] Install Finished
Version - 5.0.0.3324 Build 472350
Description - VMware vCenter Server Appliance
Update to version 5.0.0