LAN clipboard: get the two Macs reaching each other first

Set up a LAN clipboard on a network you control

For a first setup, use a home or office LAN you can make decisions about. Install Deskferry and open it on both Macs, use Add Mac in the administrator's group to invite the second one, approve it as administrator, then select that same group at both ends.

Say yes when macOS asks for local network access. Without it the other Mac will not appear at all, and you will spend the next ten minutes debugging a permission dialog you dismissed. On a managed computer or a managed network, ask whoever runs it to check the policy — do not switch off security controls to force a pairing through.

No device listed? Test whether they can reach each other

Guest Wi-Fi, wireless client isolation and separated subnets can each let a Mac browse the web perfectly while blocking every packet to the machine sitting beside it. On your own network, put both Macs on the same non-guest network for a moment and compare. In an organisation, ask the network administrator which paths between clients are permitted.

"Both Macs are online" does not satisfy a LAN requirement. There is no internet relay here: Deskferry will not carry content between a Mac at home and a Mac at the office, so when the local path is missing there is no fallback to fall back on.

Run one controlled comparison. Put both Macs on the same permitted non-guest LAN, leave the app open on each, and watch whether the invited or paired device appears. Then copy a fresh sentence and check the paste. If that works where the original network did not, you now have something concrete to report to the network administrator. Leave the app's settings alone throughout, so that a network change and a pairing change do not get tangled together.

Paired but nothing arrives? Check the current group

A Mac can be a trusted member and still be offline, and the group you joined last week is not necessarily the group selected right now. Both Macs have to be in the same current group, and connected, before a new copy is carried. To bring in a Mac that was never paired, choose Add Mac in the administrator's group, then on the other Mac choose Join a Group, select the nearby invitation, enter the six-digit code, and wait for the administrator to approve it. The first-time setup steps cover creating a group, and what happens when a code expires.

1. Select the shared group on both Macs and resume sync at each end.
2. Copy a fresh, ordinary sentence on the Mac you are sending from.
3. Paste into a text app on the other Mac, and confirm it is that new sentence rather than an earlier one.

Text arrives, files do not

Good news, in a way: once plain text crosses reliably the connection is off the suspect list, and you can narrow the search to the content itself. The file switches at both ends, the types the administrator allows, the expanded size of what you selected, whether the source files are readable. Check that the destination folder is writable and has room. One small PDF that is fully downloaded is far easier to diagnose than a mixed selection of large assets.

See copying files between Macs for the Finder actions, the size settings, and the final check of opening the received file.

Ask for help in a way that can be acted on

Tell support the macOS version on each Mac, whether they are on Wi-Fi or Ethernet, whether the other Mac is visible at all, whether plain text arrives, and the exact wording of any message you see. Leave out pairing codes, passwords and the clipboard content itself. None of that is needed to describe the step that failed, and you should not be sending it to anyone.