Sibelius error 40207 can be annoying because the message usually looks like a memory problem. You may see something like “not enough memory available” and think your computer is too weak. But many times, this error is not only about RAM.
It can happen when Sibelius cannot use your audio device, MIDI keyboard, playback engine, or a saved playback setup. Sometimes another music app is already using the same audio driver. Sometimes a MIDI keyboard is connected but not responding properly. And sometimes Sibelius is just trying to load a broken playback setting.
So don’t panic straight away. This guide will take you through the simple fixes first, then the deeper ones. Try them in order because jumping straight to reinstalling Sibelius is not always the best idea.
Why Does Sibelius Error 40207 Happen?
Sibelius error 40207 happens when Sibelius fails to complete an audio, MIDI, or playback task. The error may say there is not enough memory, but the real cause can be a locked audio driver, a MIDI device conflict, or a playback configuration that Sibelius cannot load. This is why the error can appear when opening a score, starting playback, connecting a MIDI keyboard, or using Sibelius after another music program.
Common reasons include:
- Another music app is already using the audio driver
- A MIDI keyboard or USB MIDI device is not responding
- Sibelius is trying to use the wrong audio interface
- ASIO driver is locked by another program
- Playback Configuration is damaged or too heavy
- Audio interface driver is old or broken
- Windows exclusive mode is blocking sound access
- A large score is using too many playback sounds
- Sibelius saved a device setting that no longer works
The main thing is this. Don’t only look at RAM. With this error, audio and MIDI problems are very common too.
How to Fix Sibelius Error 40207
Before you start changing settings, save your score if you can. Then close Sibelius and any other music software running in the background. It sounds simple, but it fixes more problems than people expect.
After that, follow the fixes below one by one. Test Sibelius after each fix so you know what worked.
Fix #01. Restart Sibelius and Open the Score Again
Start with the easiest fix. Close Sibelius completely, then open it again and load your score. If the playback engine or MIDI connection was stuck for a moment, this can clear it.
Also try opening a new blank score. If the blank score works but your main score gives error 40207 again, then the problem may be inside that score or its playback setup. If both files show the same error, the issue is probably with Sibelius settings, sound device, MIDI driver, or something outside the score.
If Sibelius is not closing properly, restart your computer. A restart clears stuck audio and MIDI connections that may still be running in the background.
Fix #02. Close Other Music Apps Before Opening Sibelius
This is a big one. If you opened Cubase, FL Studio, Ableton, Pro Tools, Studio One, Reaper, or another DAW before Sibelius, that app may already be using the audio driver or MIDI keyboard.
Sibelius then tries to use the same device and fails. That can trigger error 40207.
Close apps like:
- Cubase
- FL Studio
- Ableton Live
- Studio One
- Pro Tools
- Reaper
- Logic Pro
- MIDI monitor tools
- Audio routing apps
After closing them, open Sibelius first. Then test your score. If Sibelius works now, the issue was probably a shared audio or MIDI device.
If you need to use Sibelius and a DAW together, check which app should control your MIDI keyboard. Some MIDI devices do not work nicely when two programs use them at the same time.
Fix #03. Unplug Your MIDI Keyboard and Test Sibelius
If you use a MIDI keyboard, digital piano, USB MIDI cable, drum pad, or audio interface with MIDI ports, unplug it for a test. Then open Sibelius again and try the same score.
This does not mean your MIDI keyboard is broken. It just helps you find the cause. If Sibelius works when the device is unplugged, then the error is likely linked to that device or its driver.
Now plug the device back in, but use a direct USB port on your computer. Avoid cheap USB hubs for this test. Also try another USB port if possible. Small thing, but it can make a difference with MIDI devices.
Fix #04. Change the Audio Engine Interface in Sibelius
Sibelius needs a working audio output to play your score. If it is trying to use a bad ASIO driver, disconnected interface, or wrong sound device, error 40207 can show up.
Open Sibelius and try this:
- Go to Play.
- Open Playback Devices.
- Click Audio Engine Options.
- Find the audio interface or driver setting.
- Change it to another option.
- Try your normal speaker output, Primary Sound Driver, DirectSound, WASAPI, or another safe option.
- Close and reopen Sibelius.
- Test playback again.
If Sibelius was using ASIO, switch away from ASIO for now and test again. ASIO is useful for music work, but it can be picky. If another program is using that driver, Sibelius may not get access to it.
If the normal speaker option works, then your issue is probably with the ASIO driver or audio interface setup.
Fix #05. Use a Basic Playback Configuration
A broken Playback Configuration can also cause Sibelius error 40207. This can happen when Sibelius tries to load a sound library, MIDI output, or saved device that is no longer available.
Go to Playback Devices and choose a basic setup. Try something simple like General MIDI or a light Sibelius Sounds option if available. Then open a small score and test playback.
If the basic setup works, your old playback configuration may be damaged or too heavy. You can create a fresh playback configuration instead of editing the old one. That way, if something goes wrong, you still have your old settings saved.
This fix is useful when the error happens only with certain scores or only when playback starts.
Fix #06. Update Your Audio Interface Driver
If you use an external audio interface, check its driver. Old or broken drivers can stop Sibelius from using sound properly. This can happen after a Windows update, macOS update, or after installing another music app.
Go to the official website of your audio interface brand. Download the correct driver for your exact model. Don’t use random driver updater apps. They can install the wrong driver and make the issue worse.
After installing the driver, restart your computer. Then connect the audio interface and open Sibelius again. Test with a blank score first, then test your main score.
If the problem started right after a new driver update, you may need an older stable driver. Only do that if the official brand website provides it.
Fix #07. Check MIDI Drivers and Old MIDI Devices
MIDI drivers can quietly cause problems. You may not see a clear warning, but Sibelius can still fail when it tries to use that device.
Check your MIDI setup and remove anything you do not use anymore. Old virtual MIDI tools, duplicate keyboard entries, and disconnected USB MIDI devices can confuse Sibelius.
Things to check:
- Old MIDI keyboards still showing in the system
- Duplicate MIDI ports
- USB MIDI cables that no longer work
- Virtual MIDI drivers you installed before
- MIDI interface drivers with warning signs
- Audio MIDI Setup on macOS
- Device Manager on Windows
After changing MIDI drivers or devices, restart your computer. Then open Sibelius without any other music app running. Keep it simple while testing.
Fix #08. Turn Off Exclusive Mode on Windows
Windows has a setting that lets one app take full control of your sound device. This is called exclusive mode. It can be helpful sometimes, but it can also block Sibelius.
If another app takes control of the sound device first, Sibelius may fail when it tries to use it.
Here is how to check it:
- Right-click the speaker icon in Windows.
- Open Sound settings.
- Go to More sound settings or Sound Control Panel.
- Select your playback device.
- Click Properties.
- Open the Advanced tab.
- Uncheck Allow applications to take exclusive control of this device.
- Click Apply.
- Restart Sibelius.
This fix is mostly for Windows users. If you noticed the error after using a DAW, browser, recorder, or voice chat app, this setting is worth checking.
Fix #09. Check RAM and Large Score Problems
Yes, the error mentions memory, so RAM still matters. But check this after the audio and MIDI fixes. A lot of people waste time checking memory first when the real issue is a driver conflict.
Open Task Manager on Windows or Activity Monitor on macOS. See if your computer is already using too much memory. Close heavy apps like browsers with many tabs, video editors, DAWs, games, and screen recorders.
Then open Sibelius and test a small score. If a small score works but a large score fails, the large score may be using too many sounds or instruments. You can try a lighter playback setup, remove unused instruments, or split the work into smaller sections if needed.
Also check your storage space. Low disk space can make programs act strange because they need space for temporary files and cache.
Fix #10. Reset Sibelius Playback Settings
If Sibelius keeps using a broken audio or MIDI setup, resetting playback settings can help. This is more advanced, so don’t rush it.
Sibelius can remember old devices, saved audio engines, playback configurations, and MIDI ports. If one of those saved settings points to a device that is no longer connected, the same error may keep coming back.
Before you reset anything, take screenshots of your current playback settings. Write down the audio device and playback configuration you use. This makes it easier to rebuild your setup later.
A safer first step is to create a new Playback Configuration inside Sibelius. If that works, you may not need to touch deeper preference files. If it does not work, then look for reset steps for your exact Sibelius version because older Sibelius versions and Sibelius Ultimate may store settings differently.
Fix #11. Update Sibelius and Avid Link
If you are using an old version of Sibelius, it may not work well with newer audio drivers or newer system updates. This can lead to strange playback errors, including error 40207.
Check for Sibelius updates. Also update Avid Link if your version uses it for updates or license control.
A simple update order can be:
- Back up your scores.
- Close Sibelius.
- Close other music apps.
- Update Sibelius.
- Update Avid Link if needed.
- Restart the computer.
- Open Sibelius and test again.
Avid Link is not usually the main cause of error 40207. But if Sibelius also has opening, activation, or license issues, then it is worth checking.
Fix #12. Reinstall Sibelius as a Last Option
Reinstalling Sibelius should be the last fix. Not the first. If the issue is your MIDI keyboard, ASIO driver, or Windows sound setting, reinstalling Sibelius may not help at all.
Still, if you tried everything and the error is still there, a clean reinstall can help remove damaged files or broken settings.
Before reinstalling, back up:
- Your Sibelius scores
- Custom templates
- Sound sets
- Plug-ins
- Playback settings if possible
- Avid account and license details
After reinstalling, do not connect everything at once. Open Sibelius first and test a blank score. Then connect your MIDI keyboard. Then test your audio interface. Add things slowly, one by one, so you can catch the real cause if the error comes back.
How to Prevent Sibelius Error 40207 Again
Once Sibelius starts working, keep your setup simple and stable. This error often comes back when users keep changing USB ports, open a DAW before Sibelius, or leave old MIDI tools installed.
Try these habits:
- Open Sibelius before opening your DAW
- Use the same USB port for your MIDI keyboard
- Keep your audio interface driver updated
- Avoid weak USB hubs for music devices
- Keep one simple playback setup as a backup
- Close unused music apps before using Sibelius
- Restart your computer if MIDI devices stop responding
- Remove old MIDI tools you do not use
It may sound boring, but music software likes a clean setup. Sibelius works better when it knows which audio and MIDI devices it should use.
Final Thoughts
Sibelius error 40207 looks like a memory error, but it is often not that simple. Many times the real problem is an audio driver, MIDI keyboard, ASIO conflict, or broken playback setting.
Start with the easy fixes. Restart Sibelius, close other music apps, unplug MIDI devices, then check the audio engine and playback configuration. After that, move to drivers, Windows exclusive mode, updates, and reinstall only if nothing else works.
Did your Sibelius error 40207 appear after connecting a MIDI keyboard, opening a DAW, or loading a certain score? Share that detail in the comments so it is easier to find the real cause.