www.makemkv.com

On Windows when creating a directory MakeMKV should remove trailing spaces. When you create folders named "Disk Title " windows lets you do it, and properly saves the files, but you will have difficulties accessing the folder and you cannot delete it or rename it using Windows Explorer. (The current workaround I use is to rename it via 7Zip) It would be much cleaner if the program automatically removed them.

You are probably saving to folders that are subject to the (relatively new) Windows Ransomware protection. This prevents "unauthorized" alterations to files after they're created.