What are xlsb files?

[JenniferMurphy]

My stupid Surface Book just crashed. Unfortunately, I had several workbooks open. When it rebooted and I opened Excel, it showed 7-8 files in the Document Recovery panel. Most say [Original]. Two of these also have an [AutoRecovered] version with a filetype of .xlsb. One, the top one, has a very long name that starts with "Sign in to your Microsoft account..." and then what looks like a bunch of hex characters and %foldername% strings.

I have never intentionally used xlsb files before. Why is the recovery program doing this? And what should I do?

And what's with that top file? What should I do with that one.

???

 

[Coding4Fun]

xlsb = Excel Binary Files
xlsb

It sounds like perhaps you are using one drive and one of the auto recover files is in your one drive or a cloud location and it wants you to sign in to recover it but just a guess.

It should give you the option to open them to view them and decide if you want to save a copy of the recovered file.