Im writing a tool that goes through users emails and processes them in some way. Once processed, I would like to modify the email in some way to display the user viewing it in outlook that it was processed, so that it's easy for them to see which have and haven't been. A few ways I've thought of doing it:
create custom category and set category on processed emails. This is an ideal solution but requires the user to give me access to their calendar to play with their categories - not feasible in my situation
modify the email in some way (eg subject) - would rather leave emails in tact as users may still use them e.g. to respond to
flag them - not reliable as they may already be flagged and don't want to override.
Are there any other possible things I can do to an email to display to the used its been processed? I basically have owner access on the emails, but nothing else in their mailbox.
