After upgrade to Symantec DLP version 16.0.2 RU2, user can't download incident attachment when its filename is written using a non-Latin alphabet (i.e. Cyrillic, Chinese, Arabic etc.).
If the filename is using a Latin alphabet, i.e. English, the user can download it with no error.
16.0.2 RU2
Related bug CRE-18122 - Unable to open an attachment that includes non-Latin characters from the Incident Snapshot page.