mac-to-pc chats

Kevin Justie kjustie at
Thu Jun 20 16:12:02 EDT 2013

I've now added two more PCs to the network, and and it turns out (as you suggested) that the inability to initiate chats is not limited to Macs.

The three PCs are brand new, Windows 7 SP1.  Only difference is that 2 are (identical) desktops and one is a laptop.  Have re-checked to confirm that all PCs and Macs have the same subnet settings, and the same firewall settings (Bonjour and Pidgin, opened at "domain" and "home/work" levels (because the Macs are not on the domain)).

--  10.8 Mac CANNOT initiate chat with the two desktops (regardless of whether they're logged in as a regular user or an admin, which does affect PC-to-PC chats; see below).   Macs with 10.6 or older CAN initiate chats to all PCs (don't have any at 10.7 to test).

--  10.8 Macs CAN initiate chat with the laptop.

--  All three PCs CAN initiate chats with 10.8 or 10.6 Macs.

--  The two desktops CAN each initiate chats with each other and with the laptop.

--  The laptop CANNOT initiate chats with the desktops; in fact, Pidgin almost always crashes when I try to initiate chats with the desktops from the laptop.

--  All of the above are with the PCs logged in as a normal, domain-based user.  If, however, I log in as a local admin instead, then the laptop CAN initiate chats with the desktops.  It turns out, however, that it's only the laptop being logged in as admin that makes the difference:  if the laptop is logged in as a user and the desktop as an admin, only the desktop can initiate the chat (same as when both are users), but if the laptop is logged in as admin and the desktop as a user, then either one can initiate the chat.

And then to throw in yet another twist, the laptop's "regular" user is also an domain admin, but it takes being logged in as a local admin to enable the laptop to initiate chats with the desktops.

So, the bottom line is that all PCs can initiate chats to the Macs, the Macs can initiate chats to the laptop but not to the desktops, and the desktops can initiate chats to each other, but not to the laptop -- unless the laptop is logged in as local admin.

Does this make any sense, or provide any clues as to what the underlying issue may be?


> On Mon, Jun 17, 2013 at 5:37 PM, Kevin Justie <kjustie at> wrote:
>> Hi Daniel,
>> Tweaking the firewall worked -- thanks! -- but only as long as the PC was using DHCP.  That's how it was set up (by somebody else), but I prefer to have static IPs for staff computers, and when I changed it to a static IP, the initial chat messages from Macs were again ignored/not received.  Computers are all on the same network:  Macs are 172.16.3.x, DHCP gave the PC a 172.16.4.x number, and I changed it to a 172.16.7.x number.  Why would an IP change like this affect those Mac-initiated messages, if the firewall is no longer blocking them?
>> kevin
> Please reply to the support mailing list, not to me directly.
> I'm pretty sure that the Dynamic vs Static IP address assignment is
> something of a red herring (as is the Mac vs. PC part of the
> situation).
> My guess is that there's some sort of routing or network restriction
> that's preventing connectivity between the machines.  It's hard to
> guess what's going on in your network that would specifically be
> problematic - I'd make sure that the IP ranges are on the same subnet
> (Bonjour relies on this to be the case).
> -D

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