You can file share between any version of the Mac OS from your system. They were incorrect in stating you could not share a file between OS X 10.7 and 10.6.
If you want to share files between two systems, go to the Sharing system preferences and enable File Sharing on both (check the box next to this service). Then plug an Ethernet cable between them, or ensure they are otherwise on the same network via WiFi or Ethernet, and you should see them appear in the sidebar of the Finder for each system. Clicking on this computer in the sidebar will show the available "Public" folders for accounts on the respective system, and by authenticating you will be able to see the resources available to the account by which you have authenticated. This usually includes the Macintosh HD, the user account, the user account's public folder, and any attached external hard drives.
Using these resources you can copy files to and from the system.
In addition to these, OS X 10.7 or later supports AirDrop on more modern systems, or you can use internet-based sharing such as DropBox as an intermediary for transferring some files. Additionally, you can use a USB thumb drive as a similar but local intermediary for file transfers.
Hi Kessler, thanks for the response.
I have 10.7.5, but cannot see this Airdrop feature, despite having checked various kb articles and attempting to go through it with Apple Support, who simply passed me to another colleague after a long delay. Neither could explain its absence. I have spent several hours today researching this, but finding the new suport area difficult to navigate in any meaningful manner.
Also, I am unclear how one uses Airdrop to share files with an older machine, such as 10.6?
The way you describe file sharing is pretty much the way I am familiar with using it. However, when I attempt to connect to one of the machines, the icon for it first of all shows a timeout error, and has now vanished. I have switched on and off filesharing on both machines, and restarted them to no avail.
USB drives (and floppy, zip and CDs as recommended by the Apple kb) are inconvenient for project folders that need regular updating. I use dropbox, but this is not always ideal as we had to log out one dropbox user to allow a diffrent account to connect on the same machine. This leads to privacy issues.
Perhaps more specifically, why does the mac in question disappear from the network and sidebar? This worked perfectly when both machines were on 10.6.
Airdrop will only be available for Macs that support it. If your Mac cannot use it then it will not show as an option. Airdrop can only be used to share to another Airdrop-capable machine.
To fix the sidebar issue, you might try going to the Finder preferences when the servers disappear and try toggling the option to show or hide them in the sidebar. Do this for both "Connected servers" and "Bonjour computers" to see if that helps the situation at all.
My machine is running 10.7.5. The kb articles explain where I should see it, and even Apple Support were unable to resolve that issue. It's a paid for upgrade - at their advice. Not sure what to do next…
However, conventional file sharing is far more the way I would expect to work (as this is the way I have connected since System 7!)
I tried switching those items on and off (and confused as their is an iDisk option here??), but the shared machine does not reappear. It also no longer appears in Network as would be expected. It is definitely on the network, both machines are. They are connected to the same router and the IP addresses (and activity lights) for each can be seen.
Would trashing the preferences for file sharing help or anything?