Fix: ERROR_INVALID_EXE_SIGNATURE 191 (0xBF)

Running the app in compatibility mode is the quickest fix

4 min. read

Updated onNovember 7, 2024

updated onNovember 7, 2024

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For fixing Windows errors, we recommend Fortect:

Fortect will identify and deploy the correct fix for your Windows errors. Follow the 3 easy steps to get rid of Windows errors:

TheERROR_INVALID_EXE_SIGNATUREWindows system error, with code191 (0xBF), arises when running an app incompatible with the Windows architecture, say a64-bitapp blocked on a32-bitOS, due to problems with the signature.

The error message reads,191 (0xBF) Cannot run %1 in Win32 mode.

Before you proceed, check for app compatibility with the OS, scan the PC for malware, and install any pending Windows updates. For most, this should do the trick!

How can I fix ERROR_INVALID_EXE_SIGNATURE?

1. Check the path

When faced withERROR_INVALID_EXE_SIGNATURE 191 (0xBF), your primary approach should be to verify whether the path in the code is correct. In many cases, during code execution, it tried to fetch an incorrect path or folder that was inadvertently created.

Also, the presence of multiple executable(.exe)files can trigger the Windows system error. So, make sure you only have one!

2. Run the app in compatibility mode

3. Repair the corrupted system files

If your PC hascorrupted system files, it’s likely to triggerERROR_INVALID_EXE_SIGNATURE Cannot run %1 in Win32 modeand other system errors. To fix this, run theDISM(Deployment Image Servicing and Management)and SFC(System File Checker)scans, which will replace all such problematic files with their cached copy!

4. Update all the drivers

If you get191 (0xBF) Cannot run %1 in Win32 modefor a driver file,updating the driverswill do the trick. And in case Windows can’t find a better version, head to the manufacturer’s website, find the new releases, andmanually install the latest driver!

5. Reinstall the affected app

If a quick removal doesn’t help fixERROR_INVALID_EXE_SIGNATURE, I recommend using atop-rated uninstaller softwareto delete all leftover files, app cache, and Registry entries that might trigger conflicts even post-uninstallation.

6. Perform a system restore

If you can’t identify the underlying cause behindERROR_INVALID_EXE_SIGNATURE,performing a system restorewill allow you to revert all conflicting changes made in the recent past, including the one triggering the error.

In case nothing else works, you can alwaysreinstall Windows, but this should only be used as a last resort. Remember, a reinstall will also fix other similar issues, preventing reappearances of the error!

For any queries or to share which fix worked for you, drop a comment below.

Fix: ERROR_INVALID_EXE_SIGNATURE 191 (0xBF)#

How can I fix ERROR_INVALID_EXE_SIGNATURE?#

1. Check the path#

2. Run the app in compatibility mode#

3. Repair the corrupted system files#

4. Update all the drivers#

5. Reinstall the affected app#

6. Perform a system restore#