If you MDrivenServer log contains errors like

String or binary data would be truncated

You have OCL code or a part of your system in general that puts a too long text into a attribute and then tries to save it.

The rest of the message might be like

@errorinfo=S_OutgoingEmail.SS_OutgoingEma... (length=1153) (System.String) (DbType: String)

In this example, the problem is that the serverside email action gets an exception and tries to write that error message to a too short string attribute.

You have two options, and you should probably use both;

1. Make the string attribute longer to capture what you want to store
2. Include code that makes sure you don't overflow the attribute

Use the following OCL to always ensure that you never try to write a too long string.

<attribute>.subString(1,<attribute>.maxLength-1)

For the example above;

self.errorinfo.subString(1,self.errorinfo.maxLength-1)