Windows 10: File Explorer puts uppercase letter after underscore

On my new computer, when I try to save I file, File Explorer automatically puts an uppercase letter after an underscore. I tried copy/pasting something, still nothing. It's the first time I'm seeing this, and not just me; everybody I ask about this to tells me they've never seen this. Is it because of an update? It's important to me because I have a certain way to rename the files I have to hand over to work. Has anyone ever seen this and if so, how can it be disabled?


Thank you

:)

 

Underline or underscore a letter or letters and or numbers in a online password

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how can I type in a password online and underline or underscore a letter, letters, number or numbers?

 

File Explorer- no drive letters are listed.

Original Title: File Explorer

I am trying to open File Explorer with my drives listed on the right. I only have the files in the first column and no drive letters are listed.

 

how do I underscore one letter in an email address?

I have been trying to underscore the first letter in a sky email address but without success. I have Gmail and Windows mail and have tried in both of these accounts and failed. I have done the type letter then hold down shift key but then the underscore
comes in next to the letter that I want to underscore. Help!!!!