How to fix the BthA2DP.sys blue screen (BSOD) in Windows 11 and 10

BthA2DP.sys is a Windows driver file tied to Bluetooth audio. When a blue screen names it, the Bluetooth driver was running when Windows stopped. Start by updating the Bluetooth driver from your PC maker, then reinstall or roll it back.

Facts checked on 16 October 2026. Steps written for Windows 11 (25H2 and 26H2) and Windows 10 22H2.

What BthA2DP.sys is and why a blue screen names it

BthA2DP.sys is a driver file that Windows keeps in C:\Windows\System32\drivers\BthA2DP.sys. The name reads as Bluetooth plus A2DP, the Bluetooth profile for streaming stereo sound to headphones and speakers. A reply from Microsoft support on the Microsoft Q&A site describes it as a system file driver related to Bluetooth functions.

The What failed line names the driver that was running when Windows stopped. It does not prove the file is broken. Microsoft explains that bug check 0xD1, DRIVER_IRQL_NOT_LESS_OR_EQUAL, means a kernel-mode driver tried to use pageable memory, or an invalid address, while the processor was at too high an interrupt level. Microsoft adds that in most cases the memory being used is the problem, not the level itself.

Why BthA2DP.sys crashes: the causes, most common first

Microsoft says an unexpected restart might be caused by a hardware device, its driver, or software, and that an outdated or incompatible driver is one of the most common causes of Bluetooth problems. A new PC fits this: it ships with the maker's drivers, and Windows Update may later offer a different Bluetooth driver for the same chip.

Check what the crash really says

Write down the stop code, which Bluetooth device was connected, and when the crash comes before you change anything. It picks your first fix in the table above the methods.

1. Press Win + R, type eventvwr.msc and press Enter.
2. Open Windows Logs > System and select Filter Current Log on the right.
3. Type 1001 in the event ID box and select OK. Open the newest BugCheck event: it holds the stop code and the path of the dump file.
4. Open C:\Windows\Minidump in File Explorer. Windows writes one small dump file there per crash; keep the newest ones in case you need to send them to your PC maker.
5. Right-click Start, select Device Manager, expand Bluetooth, open your Bluetooth adapter and note Driver Version and Driver Date on the Driver tab.

How to fix the BthA2DP.sys blue screen

Fixes 1 to 5 treat the Bluetooth driver and the devices around it, which is where this crash starts for most readers. Fixes 6 to 8 are the general Windows checks for when the driver is not the cause. Restart the PC after each fix and use it as you did when it crashed. If the PC crashes too soon to work in Windows, use Safe Mode first.

Fix 1. Update the Bluetooth driver from your PC maker and Windows Update

10 minutesLow riskEvery reader, and above all a new PC whose Bluetooth driver has never been updated.

Microsoft names an outdated or incompatible driver as one of the most common causes of Bluetooth problems. A driver built for an earlier Windows version can crash on a newer one, and the PC maker's driver is the one tested for your exact hardware.

1. Open Device Manager, expand Bluetooth and note the adapter name, which may include the word radio.
2. Open your PC maker's support page, enter the model name, and download the newest Bluetooth driver for your Windows version. Run it.
3. Open Settings > Windows Update, select Check for updates, then Advanced options > Optional updates and install any Bluetooth driver listed.
4. Restart the PC when the installer asks.

1. Open Device Manager. Right-click Start and select Device Manager.

   

2. Open the device's Driver tab. Expand the category (for example Display adapters), right-click the device, select Properties and open the Driver tab. Driver Date and Driver Version show what is installed now.

   

3. Update the driver. Select Update Driver and let Windows search automatically. To use a driver you downloaded from the device maker, select Browse my computer for drivers instead and point to the unpacked folder.
4. Or roll back the driver. If the problem started after a driver update, select Roll Back Driver, choose a reason and select Yes. The button is greyed out when Windows has no earlier driver to return to.

   

5. Or reinstall the driver. Select Uninstall Device. Tick Attempt to remove the driver for this device only if you want Windows to delete the driver package too, then select Uninstall.

   

6. Restart. Restart the PC. Windows detects the device again and installs a driver for it.
7. Check optional driver updates. Open Settings > Windows Update > Advanced options > Optional updates. If driver updates are listed, tick the ones you need and select Download & install.

   

These steps were written for Windows 11 24H2 and later. The full page with the other versions and what each result means: Update, roll back or reinstall a driver

Fix 2. Remove your Bluetooth devices and pair them again

10 minutesNo riskThe crash comes when a headset, speaker or keyboard connects, or after the PC wakes from sleep.

The crash is tied to Bluetooth audio, so one device that connects in a faulty way can trigger it. Removing the device and pairing it again clears the stored pairing data and shows whether a single device is the trigger.

1. Switch off every Bluetooth device you do not need, and unplug any Bluetooth dongle you added yourself.
2. Open Settings > Bluetooth & devices > Devices.
3. Select More options next to the device that was connected at the crash, then Remove device > Yes.
4. Use the PC for a day without that device. If it does not crash, pair the device again under Add device.
5. If the crash returns only with that device, update the device's own firmware if its maker offers it, or use another device.

Fix 3. Uninstall the Bluetooth adapter and let Windows reinstall it

15 minutesLow riskFix 1 did not help, or the driver looks damaged or is missing from Device Manager.

The installed driver may be beyond repair. Microsoft lists uninstalling the Bluetooth adapter in Device Manager and letting Windows reinstall it as a step for Bluetooth problems, and a fresh install replaces every file of the driver set.

1. Right-click Start and select Device Manager.
2. Expand Bluetooth, right-click the Bluetooth adapter, and select Uninstall device.
3. If a box named Attempt to remove the driver for this device (older Windows builds: Delete the driver software for this device) appears, tick it, then select Uninstall.
4. Select Start > Power > Shut down, wait a few seconds, and turn the PC on again. Windows tries to reinstall the driver.
5. If it does not, open Device Manager and select Action > Scan for hardware changes. Then install the maker's driver from Fix 1.

If the PC crashes too soon after startup to do these steps, restart into Safe Mode first, where the Bluetooth driver does not load the normal way: Start Windows or a Mac in Safe Mode

Fix 4. Roll back the Bluetooth driver and pause automatic driver updates

10 minutesLow riskThe crashes started right after a driver was installed by Windows Update.

If a new driver is what changed, going back to the one that worked removes the change. A reply on Microsoft Q&A for this driver suggests rolling back the Bluetooth driver and preventing automatic driver updates while you test.

1. Open Device Manager, expand Bluetooth, and open the Bluetooth adapter by double-clicking it.
2. On the Driver tab, select Roll Back Driver if it is available, pick a reason, and select Yes.
3. If the button is grey, there is no earlier driver. Install the previous version from your PC maker's support page instead.
4. Restart the PC and test it for a day.
5. To stop Windows from replacing the driver while you test, search for Change device installation settings in the Start menu and choose the option that stops automatic driver downloads.

Fix 5. Run the Bluetooth troubleshooter and check the Bluetooth settings

10 minutesNo riskBluetooth also drops out, the adapter vanishes for a moment, or devices fail to connect before the crash.

Microsoft's own Bluetooth article puts the troubleshooter first. It checks the Bluetooth service and the adapter, and the same article lists turning Bluetooth off and on and removing and re-adding the device as basic checks.

1. On Windows 11 open Settings > System > Troubleshoot > Other troubleshooters. Next to Bluetooth select Run.
2. On Windows 10 open Settings > Update & Security > Troubleshoot > Additional troubleshooters and run Bluetooth.
3. Follow the prompts and accept any fix it offers.
4. Open Settings > Bluetooth & devices, turn Bluetooth off, wait a few seconds, and turn it on again.
5. Make sure Airplane mode is off and the Bluetooth device is charged and in range.

Fix 6. Repair damaged system files with SFC and DISM

30 minutesNo riskOther programs crash too, or the Bluetooth driver reinstalls but the crash returns.

The old guide and the search wording point to damaged files. SFC checks protected Windows files and DISM repairs the component store they are restored from, so a damaged Windows copy of the driver set can be replaced.

1. Open an elevated command window. Right-click Start and select Terminal (Admin), or type cmd in the search box, right-click Command Prompt and select Run as administrator. Select Yes when Windows asks for permission.

   

2. Run DISM first. Type the command below and press Enter. DISM downloads clean copies of damaged components from Windows Update, so it can take several minutes. Wait until it says The operation completed successfully.

   DISM.exe /Online /Cleanup-Image /RestoreHealth

   

3. Run System File Checker. In the same window, type the command below and press Enter. Do not close the window until the verification reaches 100%.

   sfc /scannow

   

4. Read the result and restart. Compare the last message with the table below this guide, then restart the PC so that repaired files are loaded.

   

These steps were written for Windows 11 24H2 and 25H2. The full page with the other versions and what each result means: Run DISM and SFC to repair Windows system files

Fix 7. Remove software that hooks into the Bluetooth and system drivers

15 minutesLow riskThe crashes began after installing a security tool, a peripheral utility or a Bluetooth manager.

A security tool works at the kernel level and can clash with drivers; some users who had this crash report that removing a third-party antivirus ended it. A reader on Microsoft Q&A links the crash to a keyboard utility update, so list what changed.

1. Open Settings > Apps > Installed apps (Windows 10: Apps & features) and sort by Install date.
2. Look for a third-party antivirus or firewall, a Bluetooth manager, or a peripheral utility installed just before the first crash.
3. Uninstall one program, restart, and use the PC for a day. Do not remove several at once.
4. Windows Security takes over protection while no other antivirus is installed. Reinstall the tool afterwards from its maker if you need it.

1. Uninstall from the Start menu. Select Start > All apps and find the app. Right-click it (or press and hold) and select Uninstall.
2. Or uninstall in Settings. Select Start > Settings > Apps > Installed apps. Find the app, select More (the three dots) > Uninstall, and confirm.
3. Or uninstall from Control Panel. Some programs can only be removed here. Type Control Panel in the search box on the taskbar and open it, then select Programs > Programs and Features. Right-click the program and select Uninstall or Uninstall/Change, then follow the program's own uninstaller.
4. Restart if the uninstaller asks. Some programs finish removing their files only after a restart.

These steps were written for Windows 11 24H2 and 25H2. The full page with the other versions and what each result means: Uninstall a program or app in Windows

Fix 8. Restore Windows to a point before the crashes began

30 minutesLow riskNothing above helped, and the PC ran fine on an earlier day.

Microsoft lists restoring Windows from a restore point among the basic steps for repeated stop code errors. It returns drivers and system files to how they were on that day, without touching your documents.

1. Open System Restore. Press Windows+R, type the command below and press Enter. You can also open Control Panel > Recovery > Open System Restore. If a first page opens, select Next.

   rstrui.exe

2. Choose a restore point. Select a restore point from a time before the problem started. The Description often names the event, such as a driver or app install. If the one you need is missing, select Show more restore points (shown only when there are more).

   

3. See what will change. Select Scan for affected programs. The upper list shows programs and drivers that will be removed; the lower list shows those that might come back and may need to be reinstalled. Select Close.

   

4. Start the restore. Select Next, check the summary and select Finish. Windows restarts and applies the restore point. Do not turn the PC off.
5. Check the result. After sign-in Windows reports whether the restore succeeded. Check whether the problem is gone.

These steps were written for Windows 11 and Windows 10 (the steps are the same). The full page with the other versions and what each result means: Undo recent changes with System Restore

Still crashing: what to collect and where to send it

When a clean driver and repaired files do not stop the crash, the Bluetooth chip on the board or card may be at fault, or the PC maker has a known issue for your model. Windows 10 22H2 left support on 14 October 2025, so on that system the maker's driver is the main fix left.

• The newest .dmp files from C:\Windows\Minidump, zipped.
• The exact stop code and the line What failed, from the BugCheck event or a photo of the screen.
• The model name of the PC or laptop and the name and driver version of the Bluetooth adapter from Device Manager.
• Which Bluetooth devices you use, and when the crash happens.
• Which of the fixes above you tried.

How to keep the BthA2DP.sys crash from coming back

Check for updates after any large Windows feature update, because a driver designed for an earlier Windows version can cause trouble on a newer one. Keep the Bluetooth driver from your PC maker current, and read the maker's release notes before you install a new version.

Frequently asked questions

What is BthA2DP.sys?

BthA2DP.sys is a driver file that Windows keeps in the drivers folder under System32. The name stands for Bluetooth and A2DP, the Bluetooth profile for streaming stereo audio. A Microsoft support reply on the Microsoft Q&A site describes it as a system file driver related to Bluetooth functions. It is a normal Windows file and not malware, which is why it shows up on so many PCs.

What does What failed: BthA2DP.sys mean?

It means the Bluetooth audio driver was the code running at the moment Windows stopped. It does not prove that the file is damaged. Most often the driver set around it is outdated, mismatched or in conflict with a connected device. Updating the Bluetooth driver in Fix 1 and reinstalling the adapter in Fix 3 help most readers.

Is BthA2DP.sys a virus?

The genuine file is part of Windows and lives in C:\Windows\System32\drivers. A blue screen that names it points to a driver problem, not to malware. If you see a file with this name in another folder, run a full scan with Windows Security. Do not download a replacement file from a site that offers drivers or system files.

What does DRIVER_IRQL_NOT_LESS_OR_EQUAL mean with BthA2DP.sys?

Microsoft explains that a kernel-mode driver tried to use pageable memory, or an invalid address, while the processor was at too high an interrupt level. In most cases the problem is the memory being used, not the level. With BthA2DP.sys this usually points to a mismatched or damaged Bluetooth driver, so start with Fix 1 and Fix 3.

Why does my new PC crash with BthA2DP.sys?

A new PC ships with drivers chosen by its maker, and Windows Update may later offer a different Bluetooth driver for the same chip. Microsoft says an outdated or incompatible driver is one of the most common causes of Bluetooth problems. Install the newest Bluetooth driver from the maker's support page (Fix 1). If the new PC keeps crashing, it is under warranty, so report it.

Why does the crash come when my headphones connect?

The driver handles the connection to Bluetooth audio devices, so a device that connects in a faulty way can trigger a fault in it. On Microsoft Q&A a reader reports the crash when earphones with a multipoint feature switched to the PC during a restart. Remove the device and pair it again (Fix 2), and test with the multipoint feature off.

What does BthA2DP not verified mean?

It is not a message from Windows. Crash analysis tools print lines such as Unable to verify timestamp for a driver when they cannot match a file with its symbols. A reply on Microsoft Q&A shows such a line for a different Bluetooth driver. The warning alone does not show a bad file, so treat it as a pointer to the Bluetooth driver set.

Can I delete BthA2DP.sys to stop the blue screen?

No. It is a Windows driver file, and removing or replacing it by hand does not remove the cause. A file copied from a download site is a risk of its own. Update, reinstall or roll back the Bluetooth driver instead (Fixes 1, 3 and 4), and repair Windows files with SFC and DISM (Fix 6) if that does not help.

The PC crashes right after I log in. How do I fix it?

Start the PC in Safe Mode, where the Bluetooth driver does not load the normal way. Microsoft lists Safe Mode as a basic step for repeated stop code errors. There, uninstall the Bluetooth adapter (Fix 3) or roll back the driver (Fix 4), then restart normally. One user on Microsoft Q&A reports that this was the only way to reach the desktop.

Is it safe to use Bluetooth after this crash?

Yes, once the driver is current and the crash has stopped. Bluetooth itself is not at fault. If a certain headset or speaker brings the crash back, keep it off the PC and check its maker for a firmware update. A wired headset or a USB audio adapter works as a fallback while you wait for a driver fix.