Clean install, means un-install all previouse versions

[steph Arnott]

If you do not, you will have problems, like cliches, crashing, etc

[Dresden Ceriano]

Do you have a question about this or are you just stating it to remind yourself?

...Dres

[Lindal Kidd]

Yes, that's what it means.  But HOW you do it is important.  There are some files that need to be deleted that simply running Windows' uninstall function will not delete.  They must be taken care of manually.  See this information:

http://community.secondlife.com/t5/English-Knowledge-Base/How-to-uninstall-and-reinstall-Second-Life/ta-p/1375231