What happened when you tried to install the older version? Did you get an error message?

If you got a message saying that there was a version of LW still running, open Task Manager (ctrl/alt/del) & see whether there's a LW process running. If there is, end the process. Now try to reinstall.

How did you remove LW? If you removed via Add/Remove programs, that's the wrong way & can lead to problems. In that case, use your computer's search to look for all files & folders with limewire in the name & delete whatever you find. Restart your computer & then try to reinstall LW.

When I tried to reinstall the older version it would download the newer one. I did search the folders and removed everything that read limewire and tried to reinstall it but it still won't connect. I want to restore back to the factory settings. Will that help?

So you now have the 4.12.6 installed?

Try this first, sometimes preferences can get corrupted after switching from version to version & it can lead to connection problems.
Delete LW's preferences folder when LW's properly closed. See point 3 here & also point 2 if you've used older versions of LW in the past (there could be a folder in either location).
Fixes for LimeWire
This will kill all of your settings within options, you'll have to go back through afterwards & reset things. If you're not sure of your settings, go through LW's tools > options & write them all down, so that you can reset things later.
LimeWire Pref Folder in Vista

If that doesn't fix things for you, please give us your details
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