Company Home -> Create Space -> TEST -> More Actions -> Manage Content Rules -> Create Rule -> All Items -> Add to List -> Next -> Add aspect to item -> Set values and Add -> Classifiable -> Ok -> Next -> Title (Add category) -> Apply rule to sub spaces -> Next -> finish.
Now add two files say "unix_java.txt" and "testTilda.txt" by Add Content option. Once the files being uploaded , you will see for the "" character file , it still asks "Allow Categorization" in the details page where "unix_java.txt" got categorization rule applied. Why the the rule has not been applied to the file with "~" character?
Please have a look on screen shot for better understanding. You can use attached file for uploading on your dev envt.
Same issue doesn't affect filenames starting with "#" and "&".