cannot open .BMP files on my Mac

[Sig_Dude]

I'm unable to open .BMP files on my Mac. Is this normal? Please see the example error message below. I know that this particular file is good as I can open it on a PC. Thanks for any replies.

 

[gilby101]

This is not normal. I can open all the BMPs (about 80) on my Mac.

On the face of it, the error message says what is wrong.

Is this for one particular BMP? Or is it an error for all BMPs from different sources? Have you tried opening with another app?

 

[Sig_Dude]

This is not normal. I can open all the BMPs (about 80) on my Mac.

On the face of it, the error message says what is wrong.

Is this for one particular BMP? Or is it an error for all BMPs from different sources? Have you tried opening with another app?

Thanks for the reply.

It has now happened with multiple .BMP files. The one I referenced in my OP is unremarkable. See its Windows 11 properties below:

 

[ab22]

12.6 Monterey had a known problem with certain .bmp files, below some color depth. If that doesn't apply, try some samples

Microsoft Windows Bitmap Sample Files

 

[Fishrrman]

Have you tried opening them with Graphic Converter?

GraphicConverter 12 App - App Store

Download GraphicConverter 12 by Lemke Software GmbH on the App Store. See screenshots, ratings and reviews, user tips, and more games like GraphicConverter 12.

apps.apple.com

 

[chown33]

Are any of your .BMP files appearing properly in Quick Look?

View and edit files with Quick Look on Mac

On your Mac, use Quick Look to view, rotate, mark up, or trim files without opening them.

support.apple.com

 

[Sig_Dude]

Have you tried opening them with Graphic Converter?

GraphicConverter 12 App - App Store

Download GraphicConverter 12 by Lemke Software GmbH on the App Store. See screenshots, ratings and reviews, user tips, and more games like GraphicConverter 12.

apps.apple.com

Negative. It appears to be payware.

Thank you for the suggestion, though.

 

[Sig_Dude]

Are any of your .BMP files appearing properly in Quick Look?

View and edit files with Quick Look on Mac

On your Mac, use Quick Look to view, rotate, mark up, or trim files without opening them.

support.apple.com

Doing a QuickLook results in:

 

[Sig_Dude]

12.6 Monterey had a known problem with certain .bmp files, below some color depth. If that doesn't apply, try some samples

Microsoft Windows Bitmap Sample Files

I am able to open all of these sample .BMP files.

 

[Basic75]

I would install ImageMagick and batch-convert them to PNG.

 

[bogdanw]

Free & small viewer – qView https://interversehq.com/qview/

Free & small editor - Seashore https://apps.apple.com/app/id1448648921

Batch convert using the built-in sips https://github.com/b0gdanw/AppleScripts/blob/master/ConvertToJPG.scpt

 

[chown33]

I am able to open all of these sample .BMP files.

Would it be possible to upload one of your non-opening BMP files, attached as a ZIP file to a post in this thread. The reason for uploading ZIP is to avoid any conversion that might happen to an uploaded image file.

Maybe someone can analyze the contents and figure out the problem.

 

[gilby101]

It appears to be payware.

But free to test. Try it.

 

[judgeFire]

Negative. It appears to be payware.

Thank you for the suggestion, though.

It's old school shareware, grab a copy from https://www.lemkesoft.de/en/products/graphicconverter/download and pay when you feel it's worth it. For me, it's been an indispensable tool since 1992, when it was first released; a quintessential Mac classic.

 

[Fishrrman]

OP:

Find one or two examples of files that won't open for you.
Post them here as attachments.
Someone here will find the answer and tell you what to do.