Fix a bug on no setting file

[HashidaTKS]

When a setting file does not exist, we unintentionally regarded the content as "404 Page not found", but we should regard it as an empty setting.

Test

• Execute test\run-test-server\run-test-server-.bat
• Remove test\run-test-server\congis\*.txt
• Open Outlook
• Open FlexConfirmMail setting dialog
• Select "Configure Trusted Domains and Addresses" tab
  • Confirm that the template for no policy setting or only current user config are used.
  • Confirm that "404 Page not found" is not shown,
• Select "Configure Unsafe Domains and Addresses" tab
  • Confirm that the template for no policy setting or only current user config are used.
  • Confirm that "404 Page not found" is not shown,
• Select "Configure Unsafe Files" tab
  • Confirm that the template for no policy setting or only current user config are used.
  • Confirm that "404 Page not found" is not shown,

[piroor]

Thanks!