Did you do a 'safe' boot & repair permissions?
Delete your LW preferences folder (however remove the old Downloads.dat file before trashing the folder.) See if LW starts up at all. If it does, close LW & put the old downloads.dat file back inside the preferences folder. Deleting LW Preferences folder in OSX

If still not working, you could try the LW beta LimeWire 5.2.2 (Beta) - Lime Wire & even try one of the older versions see if it works at all. There is a Pro Beta version found at right side of your Pro download page, likewise for older versions. But to install an older version you'd need to first remove the install limewire.pkg file from the Library -> Receipts folder.

Hi! Thanks for your fast answer !!
I did remove ALL of the LW Pro ; throw away the install.pkg, repair authorisations, checked disk. Réinstalled a "normal" version 5.1.3 but still no effect. The icon bounces onces and that's it. I tried to move the Java in their preference file : nope;
The only change between yesterday and this morning was the apple Java update. Yesterday LW worked perfectly, after update it doesn't even want to launch...

I'll try the beta version and let you know.

Hello again !
I downloaded and installed LW5.2.2 beta and it works ! But I don't remember the email adress I used to get my former Pro version (5.1.2) so I guess I'll have to pay again....snif !!

I'm sorry to come back with bad news.... I did buy today which I thought to be the 5.2.2 Pro version, but it found out to be the 5.1.3 version. Where can I find the 5.2.2 Pro beta version without paying again ??
Since I did an Apple upgrade for Java this morning, ( Mac OS 10.5.7) my older version (5.1.2 Pro) refuses to launch. Same for 5.1.3 version. Only the 5.2.2 version works well, but I got the 5.1.3 version, while I thought to pay for the 5.2.2 version. Not really clear your download pages... As for pesonal download page ??? Never seen

Thanks in advance for your explications and help !!

You will see a link half way down to the right.

Thanks for your help. I really appreciate ! Got it downloaded and it works fine. Just one remark : The LW icon in the dock is not stable, the red spot is not round and the numbers are aside...
Not really important, but might as well say it.
I will come back in a couple of days with my impressions about this beta.
Have a nice day !