amm123

“OpenSubspace on macOS Sonoma: Beating Gatekeeper and Fixing File Access for Good”

Published on

OpenSubspace (app) on macOS: the “Can’t Be Opened” Rabbit Hole I Didn’t Expect

I spent last night installing OpenSubspace (app) from OrchardKit on a MacBook Air M2 running macOS Sonoma 14.3, and what should have been a two-minute setup turned into a proper Gatekeeper standoff.

From the slug, it’s clearly a productivity/office tool — something in the “workspace/client” category — and that tracks with what I saw: a standalone build, not from the Mac App Store. Clean bundle, dragged into /Applications, double-clicked… and macOS immediately blocked it:

“OpenSubspace can’t be opened because Apple cannot check it for malicious software.”

Classic Gatekeeper.

I’ve dealt with this dozens of times, but Sonoma has become a little stricter, especially with unsigned or lightly signed builds. Here’s how it unfolded.

First Attempt: The Usual Right-Click Trick (Didn’t Stick)

Normally, you can bypass Gatekeeper by right-clicking the app → Open → confirm the dialog. That tells macOS you’re intentionally launching it.

I did that. It opened once.

Closed it. Tried again. Blocked again.

That’s when I knew this wasn’t just a basic quarantine flag. Something deeper was happening — likely extended attributes combined with a hardened runtime mismatch.

Apple documents the behavior here in their official Gatekeeper explanation: https://support.apple.com/en-us/HT202491

The key detail: macOS applies a quarantine attribute (com.apple.quarantine) to apps downloaded from the web. Sometimes removing it manually is cleaner than fighting the GUI.

What Was Actually Going On

When I inspected the bundle in Terminal:

xattr -l /Applications/OpenSubspace.app

Sure enough, quarantine metadata was attached.

But here’s the nuance: simply using Finder’s “Open Anyway” didn’t persist the override. That can happen if:

  • The bundle was moved between folders after first launch
  • The signature doesn’t fully validate
  • Or the binary inside the .app bundle is flagged separately

Given this was a direct download and not an App Store build (there’s no official listing I could find under https://apps.apple.com/search?term=OpenSubspace), the system treated it cautiously.

Apple’s developer docs explain how notarization and signing interact with Gatekeeper: https://developer.apple.com/documentation/security/notarizing_macos_software_before_distribution

If a build isn’t notarized, macOS will block it unless explicitly allowed.

What Actually Fixed It

Here’s what worked cleanly and permanently.

In Terminal:

sudo xattr -cr /Applications/OpenSubspace.app
sudo spctl --add /Applications/OpenSubspace.app

What this does:

  • xattr -cr removes all extended attributes (including quarantine flags)
  • spctl --add explicitly whitelists the bundle in macOS security policy

After that, the utility launched consistently. No more warnings. No more re-blocking after relaunch.

This is the part most “just open it” advice skips. The GUI method sometimes only whitelists temporarily.

A Secondary Issue: File Access Permissions

After launching successfully, I ran into something subtler. The app opened, but it couldn’t read files from my Documents folder. No crash — just silent failure. Import dialog would spin, then nothing.

Sonoma’s Privacy & Security model is stricter now. Even if an app launches, it doesn’t automatically get access to user directories.

Fix:

System Settings → Privacy & Security → Files and Folders Enable access for OpenSubspace.

Immediately solved the import issue.

Apple’s documentation around file access entitlements is clear about this behavior: https://developer.apple.com/documentation/bundleresources/entitlements/com_apple_security_filesystem

This wasn’t a bug in the tool — it was macOS doing exactly what it’s designed to do.

Why This Happens More on Apple Silicon

On Intel Macs, unsigned utilities sometimes slip through with fewer complaints. On Apple Silicon (M1/M2), the chain of trust is more aggressively enforced.

My M2 Air is particularly strict with anything downloaded via browser (I used Safari, which absolutely applies quarantine flags). If you download via curl or a package manager, behavior can differ slightly.

This isn’t OrchardKit-specific — it’s just modern macOS being modern macOS.

The Resource That Helped

While sorting this out, I came across this page covering macOS operational quirks around the OpenSubspace build, and it lined up with what I was seeing: https://smohamad.com/office-and-productivity/92564-opensubspace.html

It wasn’t fluff — it reinforced that the issue was system-level, not corruption or a broken installer.

That saved me from wasting time redownloading the archive three times, which I absolutely tried first. Didn’t change anything.

What I’d Do Differently Next Time

If I’m installing a direct-download productivity client on macOS again, here’s the quick checklist I’ll follow:

  • Move the app to /Applications before first launch
  • Remove quarantine flags immediately (xattr -cr)
  • Whitelist with spctl --add if needed
  • Check Privacy → Files and Folders if file access fails
  • Confirm it’s not a corrupted download with spctl -a -vv

That’s it. Five minutes instead of forty.

Final Take

OpenSubspace itself runs fine once macOS security layers are handled properly. Performance is stable on M2. No weird CPU spikes. No Rosetta translation issues. It feels like a straightforward standalone productivity build.

The friction wasn’t the app. It was Gatekeeper and Sonoma doing their job — aggressively.

I don’t mind macOS being strict. I just prefer when it’s predictably strict.

Anyway, if you install OrchardKit’s build and it refuses to open, don’t assume it’s broken. Strip the quarantine attribute, add it to the security policy, grant folder permissions, and move on with your life.

Modern macOS isn’t hostile — it just wants you to be intentional.