Red Shield: "Protected" or "Write Protected"... and how to find the latter

[MrPete]

Making progress in using iMatch. My wife (the real photographer around here) is VERY happy! (Her latest fave: the "focus" tool in the Viewer, when deciding on best-pictures. Makes it easy to see focus issues  )

ANYway... here's a strange one: A number of files have the red "Protected" shield turned on. We don't know how that happened. I want to gather them in one place and turn it off. (Not easy with 300,000+ photos in over a thousand folders  )

• Documentation says the red shield means "protected" and the "protected" collection will show them.
• BUT the protected collection is empty.

• Mousing over the shield, they say they are "Write protected", not "Protected."
• Searching these forums, Mario has said this icon is analogous to Read Only in Windows Explorer. But none of these are Read Only. And they don't show up with a (negated, hide) Read Only Files filter. Real Read only files DO show.

SO, I have a few questions:

• How do I collect the "Write protected" files? They are obviously different from "Protected"
• What's the actual purpose of the red shield? Is it supposed to have two different meanings?

Thanks!

[sinus]

The red shield means "write protected". If I protect a file in the camera, then this shield appears in IMatch.
If I want get change it to "not write protected", then I have to click on the red shield. Or use Ctrl R.

I use often Ctrl G R to assign the selected files into a new result window. Sometimes it happens to me, that I did not proper use these letters and ends up with only Ctrl R is assigned to the files. Sometimes I didn't even noticed. 

For find them all, I used, I think, the filter (File properties and there "hide read-only". 

I am not very sure though.
The proteced files in the collections is something else. 
See here: https://www.photools.com/help/imatch/fw_protected_files.htm

[thrinn]

There are two shield icons:

• The red shield means "write-protected" (or "read-only"). This is a file system level property.
• The silver shield means "file is protected". This is an IMatch feature.

The Protected Files collection shows the files with a silver shield.
To find all write-protected files, you can use the Filter Panel with a "File Properties" filter: Choose  "Hide read-only files" in combination with "Invert filter" (which means that only read-only files are displayed.