text: <s>[INST] About the Error Code 16#0013 and 16#0015 in EtherNet/IP Socket Interface. When using the PLC  1756-L73 with 1756-EN2T trying to conmmunicat with PC by a  TCP connecting as AB EtherNet/IP Socket Interface EtherNet/IP Socket Interface   ENET-AT002E-EN-P, I have succeed in Socket Creating and got the retunred Instance, but when trying to OpenConnection by MSG OpenCOnnection, the MSG show an error code 16#0013  it seems to be a problem in configuration of the source length, however I tired every possible lenth continuously and the error code changes between 16#0013 and 16#0015 as in  the document  ENET-AT002E-EN-P there shall be an airticle abou this issue called Article 1756-EN2T, 1756-EWEB sockets error 16#0020, howevery it is not found in the website. [/INST] You need to add 16 to the length of the actual string you are sending. Here is an example from a project of mine. You mention that you've already got the Instance number returned by the Create Socket instruction, as shown in the MOV instruction below.\n 1. The text being sent is in Write_Data_Out, which is a UDT that includes a 480-character string called .Buffer.\n 2. Get the length of the actual text in .Buffer (only 214 characters in my example) and add 16. Store the result in the .LEN of the MSG tag\n 3. Then execute the MSG instruction.\n </s>