Most of the times, the most boring procedure of development at least for my case is to create and translate messages in order to handle and inform the user for any kind of error or action required during the execution of a program. I'm use to create all objects in English language and then translate them to Greek.
I was wondering if there was a way to search for messages that can cover my needs without knowing the message class. Apart from the way to try to trigger the message in order to find it and reuse it ( If you are searching for a message saying " Company code & is not defined " is very easy to find it by executing transaction 'FB01' and entering a non-existing company code ) I wasn't aware of any other way to search for messages.
Finally, I found that by using transaction SE80 --> Repository Information System --> Other Objects --> Message Numbers ( Fig. 1,2 ),
there is a standard tool that let you search for messages without knowing the message class.
From that time, many of the messages that I use in programs are reused from standard message classes giving most of the times a better result and slightly reduced work effort required. Also, have in mind that since we are talking for standard messages the possibility of SAP changing the message in a future release exists. Still, I believe that such a possibility is minor and I personally prefer to use this way than to create new messages.