We have a saved .eml file which has been saved via the Save Mail Activity. We would like to reply to it via Reply to Mail (Office 365 Activity). So we are looking for a way to read the EML file as Office365Message DataType to be able to reply to it. Currently we have already tried with this custom activity Read Email from Saved File to Object - RPA Component | UiPath Marketplace . Unfortunately without success, the Reply to Mail (Office 365 Activity) gives the error message: “Reply To Outlook Mail Message: Invalid Mail Message”. Have you ever tried something similar? Is there any solution for this?