Uninstall the version that you have now (start > all programs > limewire > use the uninstall option). Next, download ccleaner & run that.
CCleaner - Home
The link below is to a version of 4.12.6 that I've hosted...download that one & see whether that installs (just in case there's some corruption in the version that you're downloading from oldversions)
LW 4.12.6 basic.exe