We tested this in multiple environment with Kentico 9.0.44. Bulk delete fail selecting the files if any of the file contains $ in file name.
We can upload the file 'SE $200 BPO 1.png' in media library and delete the file individually using recycle icon, but when we select the item by checking the checkbox, then do delete operation of selected items, it fails after confirmation dialog. Below the drop down list, we see 'Please select some files.'. Is this known bug or are we missing some configuration?
I'd suggest contacting Kentico Support and report it to them.
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