Siemens Industry Online Support
Siemens AG
Entry type: FAQ Entry ID: 12017703, Entry date: 06/28/2002

Error message: "Communications driver missing"

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Why, when setting up communication with an S7-400 do you get the message: "Communications driver missing"? You can't establish an online connection.

It is probably because the system doesn't recognize the PROFIBUS/MPI card (CP5611) on your PC. We recommend installing the CP5611 again in Settings > Control Panel. 

Open the hardware manager in Windows by choosing:

  • "Start > Settings > Control Panel > Add New Hardware"

The hardware wizard now opens. Then select the following button:

  • "Add new device or remove problem. Choose this option if you want to add a new device to the computer or if a device is not working".
  • Select the CP5611 with your cursor, click "Next" and then "Finish".

The CP5611 is now installed. Finally, in SIMATIC Manager check the settings for the PG/PC interface too. 


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