Note: Backup files before modify them and move the files outside of the Service Catalog folder.
1. On the Service Catalog server, open the ...Service Catalog\view\webapps\usm\locale\iceses\request\request_create.xml file
2. Search for <attachment_mandatory>
3. Remove where it shows {0} in the tag <attachment_mandatory>
4. Open the ...\Service Catalog\view\webapps\usm\explorer\scripts\widgets\request-add.js file and on line 570 set the following:
attachments_mandatory_validation = l10n.attachment_mandatory;
5. Restart Service Catalog
6. Delete web browser cache