Troubleshooting: Error encountered when you run multiple WebSphere Commerce Update Installer processes at one time

When you use the WebSphere Commerce Update Installer to install a maintenance package, you receive a INSTCONFFAILED message.

Problem

When you complete a silent installation, you encounter an error in the WC_installdir/logs/update/unknown.install/updatelog.txt file:
(Jan 29, 2016 2:57:04 AM), Install, com.ibm.ws.install.ni.ismp.actions.
PopulateTitleBarAction, msg1, WebSphere Commerce Update Installer V8.0.0.0
(Jan 29, 2016 2:57:04 AM), Install, com.ibm.ws.install.ni.ismp.actions.
ISMPFileDeleteAction, msg1, Deleting file: Source: /tmp/.aix_ISMP_lock____
(Jan 29, 2016 2:57:05 AM), Install, com.ibm.ws.install.ni.ismp.actions.
SettleNIFRegistryAction, msg1, Current install/uninstall process failed.
(Jan 29, 2016 2:57:05 AM), Install, com.ibm.ws.install.ni.ismp.actions.
SetExitCodeAction, msg1, CWUPI0000I: EXITCODE=1
(Jan 29, 2016 2:57:06 AM), Install, com.ibm.ws.install.ni.ismp.actions.
ISMPLogFileAction, msg1, For more information about installing components, 
see the following trace file:
/usr/WebSphere/CommerceServer80/logs/update/unknown.install/updatetrace.log.gz 
(Jan 29, 2016 2:57:06 AM), Install, com.ibm.ws.install.ni.ismp.actions.
ISMPLogFileAction, msg1, For more information about running configuration commands, 
see the following trace file:
/usr/WebSphere/CommerceServer80/logs/update/unknown.install/updateconfig.log.gz
(Jan 29, 2016 2:57:06 AM), Install, com.ibm.ws.install.ni.ismp.actions.
ISMPLogSuccessMessageAction, msg1, INSTCONFFAILED

Solution

If you encounter this problem, ensure that you do not have multiple Update Installer processes running. If there are no additional running processes, launch the graphical user interface installation and progress through the installation panels for more information.