When you want to attach a file to a CA Service Catalog request, that filename could exist of diacritic character(s).
To allow diacritic character(s) in a file name, please follow the steps below:
1. Locate the file %USMHOME%/view/conf/ESAPI.properties
2. Open this file in a text editor
3. Search for 'Validator.FileName'. Typically this property is at the bottom of the file.
4. Replace the regular expression as
Some other details/example taken from my local server:
5. Save the file and restart Catalog service. Check the new behavior.