Hello. What I believe you will need to do is rename the files after you save them.
To create a filename that is unique for each file, you can add a timestamp using the format “hhmmssff”, and you can use the Move File activity to perform the renames.
So let’s take this pseudocode to represent the logic used for this:
Get Mails: store in messages variable.
For each msg in messages
Save Attachments: output to enumerable of string, I'll call attachments
For each att in attachments
Move File: from att to Path.Combine(Path.GetDirectory(att),Path.GetFilenameWithoutExtension(att)+"_"+Now.ToString("yyyyMMdd.hhmmssff")+Path.GetExtension(att))
So something like that where you use GetDirectory, GetFilenameWithoutExtension, concatenate the timestamp to the filename and GetExtension(), then Combine to join the filepath together.
Hope that helps.