How To Fix PU751 - Communication error: System &1 (see below for details)

PU751 - Overview

• Message type: E = Error

• Message class: PU - Upgrade and Transport Log Messages

• Message number: 751

• Message text: Communication error: System &1 (see below for details)

Self-Explanatory Message

Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.

To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.

Unfortunately, there isn't any extra information in this error notice.

What else can you do?

First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).

Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.

You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.

Smart SAP Assistant

• What is the cause and solution for SAP error message PU751 - Communication error: System &1 (see below for details) ?

  The SAP error message PU751, which indicates a "Communication error: System &1," typically arises during communication between different SAP systems or between an SAP system and an external system. This error can occur in various contexts, such as during data transfer, remote function calls (RFC), or when using SAP Business Connector.
  Causes:
  
  Network Issues: Problems with the network connection between the systems can lead to communication errors. This could be due to firewalls, routing issues, or network outages.
  Configuration Errors: Incorrect configuration settings in the RFC destination or in the SAP system can cause communication failures.
  System Availability: The target system may be down or not reachable due to maintenance or other issues.
  Authorization Issues: The user or service account used for the communication may not have the necessary authorizations to access the target system.
  Protocol Mismatch: If there is a mismatch in the communication protocols or versions between the systems, it can lead to errors.
  Timeouts: