Thanks for the replies.

I have tried the above to no avail. The problem is even more intense in 64-bit mode.

I have not tried a new account (I will try that later), but I have installed WireShare 5.6.4.1 on another Mac (iMac instead of Mac mini) with the same version of Mac OS X and Java and it works with both 32- and 64-bit mode. No problem there. Such iMac had on older LimeWire Pro 4.9.8 (that is of year 2007) installed, whereas in the Mac mini with the problem newer versions of LimeWire were installed through the years, and eventually the LimeWire Pirate Edition 5.6.2 (yet it did not open since many months ago), as indicated above.

There are probably remains on the Mac mini of LimeWire and LimeWire Pirate Edition. How to remove all files associated with them? Maybe that fixes the issue.

Thanks again.

Just in case it is useful, I had installed over the years the following Gnutella clients in such Mac mini:

Acqlite
Acquisition
Cabos
FrostWire
LimeWire Pro
MactellaX_PPC
WireShare

Additionally, maybe removing Java 6 and leaving Java 7 could fix the problem. I wonder how to remove Java 6.

Finally, when you said
Delete the WireShare folder from your user preferences folder
I guess that you mean
/Users/~/WireShare

On the other hand, it seems that this problem can be fixed deleting the Limewire (in the case of such application) or WireShare preferences. But where are them in the Mac? Thanks.

Normally on MacOSX all you need to do is go to the application folder and send the particular application packages (or their program folders if they have any) into the trash & empty the trash. If you wished to keep them I guess you could zip them first & trash the unzipped programs.

I guess there is a chance opening WS is somehow triggering a reaction from one or more of those programs. I just tested WS & LPE open at same time in another account without issue however.

Preferences folder is where you suggested. Deleting preferences folder on MacOSX. The example is LimeWire, but instead find WireShare's preferences folder.

Thanks. I have also deleted
/Users/~/Library/Preferences/WireShare
to no avail. The problem persists.
Any idea?

BTW, could the issue be related to the fact that I do not have any ports open in the router?

WireShare does have UPnP (port mapping technology) but this does not work with all routers & some routers are not reliable with UPnP. For WireShare I port forwarded for my router because I found UPnP was failing after 2-3 days and I was getting a firewalled message in the Connections window.

Deleting the other gnutella programs might have an effect then.

I have deleted all related to WireShare (as far as I know):

/Applications/WireShare.app
/Users/~/WireShare
/Users/~/Library/Preferences/WireShare

and installed again WireShare. Surprisingly, the
WireShare/Preferences/Advanced/Listening Ports
has values for:
Gnutella port
BitTorrent ports

Is that normal or is WireShare taking such numbers from elsewhere, and thus creating the problem?

That's normal.
In your settings, UPnP is enabled by default and WS will attempt to automatically map the port via communicating with your router if it can find an open one. This happens when WS is first opened. This port might change each time you open WS.
However, when you port forward, the port remains static. It needs to be static (remain the same) and needs to match the port that was port forwarded in the router.
The bittorrent ports might be a built-in default, not sure about that.

There is a chance something is blocking WireShare. Firewall/router. But the question also is what is causing it to open in multiple windows.

I have found that if I block the WireShare connections when it opens (firewall prompt), then the pesky window does not show.

On the other hand, I have re-installed LimeWire (Pirated Edition) 5.6.2 from
http://www.gnutellaforums.com/gettin...e-edition.html
following the directions:
2-Connection and Security L5 June 2014 install.app
3-LimeStart Installer.app
4-LimeWirePirateEdition.dmg

and after that, opening LimeStart.app does not open LimeSire, but WireShare. How to fix it?

Just in case that gives any hint of what is going on.

That's due to LPE & WS both using the same OSX program reference which is com.limegroup.gnutella
This approach is recommended by Apple. Unfortunately LW clones or variations can get into the mix.
I used to have the same problem when I had an old LW4 clone called MP3 Rocket installed. LimeStart started to open MP3 Rocket instead. This issue is user account specific. LimeStart does not open WireShare for me.
The fix would be to remove WireShare.

LimeStart could instead use the program name, but some people rename program titles or/and move the program's location which would prevent LimeStart from finding the program. Some people might also have multiple versions of LW on their system which adds to that complexity.