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Entry type: FAQ Entry ID: 15261827, Entry date: 07/30/2003

STEP 7 V5.2 "Internal Error 2021" error message during transfer

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Why do I get the error message "Internal Error 2021" when I transfer from STEP 7 V5.2 to WinCC V5.1?

This is because you are using the new message concept (assign unique message numbers CPU-wide) in your STEP 7 project. However, this concept is not supported by WinCC V5.1.

Install WinCC V6 or create a project that uses the old message concept (unique project-wide). If you wish to switch your STEP 7 project from "CPU-wide unique" to "project-wide unique", do the following.

  1. Export the hardware information. In the HW Config click on Station and then Export... and check all the checkboxes in the "Options" field in the dialog window.


Figure 1: Exporting hardware

  1. Open the LAD/FBD/STL editor and close all the blocks there. Then select the menu option "File > Generate source..." and, in the dialog window, specify the name of the source and the project/SIMATIC station from which the source should be generated.

Figure 2: Creating an STL source ( 21 KB )  

  1. Select all the modules in the next dialog, add them to the right list and click on "OK" to exit this dialog.
    Please repeat steps 1 to 3 for each SIMATIC station.

Figure 3: Selecting blocks for the STL source

  1. Set the message concept for new projects to "Always assign unique message numbers CPU-wide" or to "Always prompt for settings" (No default).

Figure 4: Changing the message concept

  1. Create a new concept.
  2. Insert a SIMATIC station into your newly created project.
  3. Open HW Config and import your hardware information exported from the old project. Select the menu option "Station > Import..." and then specify the configuration file for your SIMATIC station. You are asked whether you wish to save the imported data; confirm with "Yes".
  4. Copy the table of icons, which is contained in the S7 program folder, from your source project and insert them into your new project.
  5. Now copy all the blocks without a yellow triangle from the source project into your new project. You can regenerate the blocks with a yellow triangle with the aid of the STL source later on.

Figure 5: Block container

  1. Copy your STL source from your source project's source folder and insert it into your new project.
  2. Select the STL source in your new project and select the "Edit > Compile" option.
    Repeat steps 6 to 11 for each SIMATIC station.

SCAN messages and user-defined diagnostic messages cannot be copied from CPU-wide projects into projects with a project-wide message concept.

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