To begin with, I noticed the Fisheye service was stopped. The Crucible had been running. I was able to stop the crucible service and un-install ok after I had done a backup using the fisheye/crucible backup service on the admin web site.
While attempting to un-install the fisheye software an error occurred that 'The JVM found at C:\Atlassian\fecru-4.5.1\jre is damaged. Please reinstall or define EXE4J_JAVA_HOME to point to an installed 64-bit JDK or JRE.'
At the command prompt, I defined 'set EXE4J_JAVA_HOME = C:\Atlassian\fecru-4.5.1\jre' and tried running the uninstall.exe and got the same error ('The JVM found at C:\Atlassian\fecru-4.5.1\jre is damaged. Please reinstall or define EXE4J_JAVA_HOME to point to an installed 64-bit JDK or JRE.')
BTW: I notice the FISHEYE_HOME = c:\Atlassian\fercu-4.5.1-2 --> that directory existed for crucible, when I un-installed crucible, that directory went away.
Ultimately, I need to install fisheye & crucible 4.6.1. How can I best do it?
UPDATE
I was able to 'un-install' FishEye by temporarily installing FishEye app on my personal PC, then copying all of the jre directory from the pc to the server; Pressed the 'Fisheye Uninstaller' and it worked. However, the 'Atlassian Fisheye' service is still registered, though it's not registered to anything. I need to find out if I can just re-install the new version... but that's another question.