We host a USA government website that allows administrators to upload documents to share with other users. These documents are usually PDFs, spreadsheets, and Word documents, but occasionally folks will upload .msg files that they've saved from Outlook.
Being a government website, we are required to verify that all documents that are available on the site are compliant with Section 508 for accessibility. Does anyone have any guidance that they use when verifying if a .MSG file is 508-compliant?