Mac says "no space left on device" but Finder shows terabytes free

You hit Save changes on a gig and the app refuses. Somewhere in the message, or in the support bundle you sent us, is the phrase no space left on device. Then you look at your Mac and it tells you there is loads of room. One performer put it exactly the way most people do: "There is actually almost 2TB free but something is wrong with my computer and it's not reading that." If your version of that is it says the disk is full but it isn't, or I have plenty of space and yet it won't save, this is the right page. The short answer: on a Mac, the number Finder shows you is not the number that decides whether a write succeeds.

The app is not deciding you are out of space

Booked Solid never estimates your free space. It asks macOS to write a file, macOS answers no space left on device, and the app repeats that answer back to you word for word. So the disagreement is between you and macOS, not between you and the app.

Here is what happens on every save. The app writes your updated gig to a temporary file first, swaps that finished file into place in one move, then reads it back to confirm every character landed exactly. That is what stops a half-written file from ever replacing good data, and if the readback does not match, the app puts the record back the way it was. Writing that temporary copy needs a little free room. When there is none, the very first step fails, the app throws the attempt away, and your record goes back exactly as it was. Nothing is lost and nothing is left half-saved.

Because that check is identical for every gig and every field, a volume with no room blocks all of them at once. That is why it feels like the app broke rather than the disk filled up. And a disk that is almost full behaves exactly like one that is completely full: the write only has to fail once.

If your error message does not mention space at all

Older builds showed "The record could not be saved safely. Nothing was reported as completed." That wording was ours and it was bad. It read as though the app wanted a completed show or a milestone logged somewhere before it would allow a save. There is no such rule anywhere in Booked Solid. It only ever meant "the save did not complete, so I rolled it back and changed nothing", and it hid the real reason. From version 1.10.1 onward the app prints the underlying reason on screen instead, so a disk problem now reads as no space left on device right there in the message. If you are still seeing the old wording, you are on an older build, and everything below still applies to you.

Cause 1: purgeable space, and this is almost always it

macOS counts space it intends to free up later as "Available". Most of that is local Time Machine snapshots, plus caches. Finder folds it into the free number and shows you the total. Finder is not lying to you exactly. It is telling you what your Mac could free up if pushed, not what is free this second.

A save cannot wait for that cleanup to happen. It needs room now. So the volume can be genuinely full at the instant of the write while Finder is still cheerfully showing terabytes. That is the single most common reason a Mac reports a huge free number and still refuses to write, and it is why a restart fixes so many of these.

Cause 2: the free space is on a different drive

Only your startup disk counts here. Almost everyone checks the big external drive first, sees it nearly empty, and concludes the app must be wrong. That number has no bearing on this problem at all. Skip it.

Two things live on the startup disk and both need room. Your Booking HQ folder is one, and unless you deliberately moved it, it sits under your user folder. The app's own files, including its settings, are the other, and they live in your user Library. On top of that, the temporary copy described above is always written into the same folder as the file it is replacing, so it draws on that same volume. Even if you did move your Booking HQ onto an external drive, a full startup disk still stops the app writing its own settings, so problems carry on even though your gig files have somewhere to land.

To see where your workspace actually lives, open Settings and find Your Booking HQ. It shows the full folder path, with a Change button next to it.

What to do, in this order

The order matters here. The first step is the one that most often ends the whole thing, so do not skip past it to go hunting for files to delete.

1. Restart the Mac. A restart on its own often releases the stuck purgeable space, and it also lets a pending app update that has been sitting unfinished finally install. It is the cheapest move available and it can clear both symptoms at once.
2. Look at the real number. Open Disk Utility (Applications > Utilities), select your startup volume in the sidebar, usually named Macintosh HD - Data, and read Available. Note how much of that figure is marked (purgeable). A large purgeable slice means local snapshots are holding the space. If you are comfortable in Terminal, df -h / prints the true free space on the boot volume.
3. Make real room on the startup disk. Deleting actual files frees space straight away, which purgeable space does not. You can see the breakdown under System Settings > General > Storage, or on older macOS under Apple menu > About This Mac > Storage. Aim for several GB free rather than a few hundred MB.
4. Quit Booked Solid completely, open it again, and try the save. With genuine room on the boot volume, saves come back. Because every blocked attempt was rolled back rather than partly written, your earlier edits were never stored, so type them in again and they will hold this time.

A full startup disk also blocks updates

If your saves started failing around the same time the app got stuck on an old version, that is one problem wearing two faces, not two problems. An update has to download and unpack itself, and it cannot do that on a volume with no room to work in. Free the space, restart, and the pending update usually lands on its own. If it still refuses once you have room to spare, work through The app is stuck on an old version or won't update.

If it still fails once you genuinely have room

Then it is not the disk, and carrying on guessing will only cost you an afternoon. Generate a fresh Support Bundle and send it in, along with the exact wording of the message you are seeing. On 1.10.1 and newer that message names the underlying reason, so between the bundle and that one line we can usually see the real cause instead of both of us speculating. The steps are in Generate a support bundle and turn on support logging.

When you write in, include three things: the Available figure and the (purgeable) figure you saw in Disk Utility, the path shown under Your Booking HQ in Settings, and the exact text of the message on screen. That is normally enough to pin it down on the first reply.

Still stuck? Submit a ticket from this help center and we will take it from there.