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Meanwhile, below is the content of that Support Article.
Special characters in file name converted to junk values
Special characters, in a file name, converts to junk values.
Steps to Reproduce
Create a UI to browse an attachment and display the file name which includes special characters.
A defect in Pegasystems’ code or rules.
When an attachment is browsed, the special characters in the file name are converted into HTML special characters.
For example, a file name with New_ABC2 - Copy (2).txt was converted into New_ABC2 - Copy $282$29.txt File.