Hi,
We are prepending\stamping a word "External" to Subject line by transport rules for all emails received from outside of organisation. The problem is that whenever the same mail is replied and received, It is again getting stamped. Can some one help me if we can avoid this by checking if the subject line has already the word external it should be ignored and should not get again stamped.
[EXTERNAL] RE: [EXTERNAL] RE: [EXTERNAL] RE: [EXTERNAL]
Thanks in advance