AOO Version 4.1.6 installation failure

[LVuser]

I have tried to install AOO 4.1.6 several times and it stops at the error "Please exit OpenOffice 4.1.6 and the OpenOffice 4.1.6 Quickstarter before you continue." I have checked the Task Manager and the Services, but I cannot find soffice or anything from Apache or anything named OpenOffice or anything close to those.
What am I missing?

[RoryOF]

In TaskManager there may be a link "Display processes for all users" (words to that effect). Try to find that and kill any soffice processes it reveals.
Note: soffice, with an initial "s".