It is read as Japanese Follows :" KONO GO EN KOKORO YORI KANSHA SHIMASU " and mean may change after what after this sentence but means: I am glad to meets you explain word by word この＝ This 　ご縁≒　meet ( God(Buddha) give a chance to send down a person for me) こころより＝from deep may heart 感謝いたします= Thanks you . It become above mean. therfore you are thinking right is one way of greeting. 　　

Hi Kimio It's a very polite expression, saying in easy word, "Glad to see you", I soppose. It's so difficult to traslate English to Japanese directly. (sorry my English isn't so good) 縁 means relationship or chance between peoples, plaeces, and everything. In this case it says the chance of meeting / knowing each other, the chance of between you and the person who sent that mail. And we use ご before nouns to express courtesy, sometimes we use お, depends on the nouns. Hope it helps you.