Connecting to an M340 with USB returns 'An incorrect structure size was detected' error message.

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Issue
Connecting to an M340 with USB returns 'An incorrect structure size was detected' error message.

Product Line
M340

Environment
Unity, Control Expert.

Resolution
Attempts to connect to the M340 using USB returns the error message 'An incorrect structure size was detected'.

This issue occurs when the 'Schneider PLCUSB Driver' is used to connect to an M340 with either Control Expert or Unity running on a Windows 10 (Build 1803) PC.

This is due to an unexpected change by Microsoft on the Windows Remote Access Services (RAS) API. It is corrected in the KB4103721 update from Microsoft released May 8, 2018.

To resolve the issue, install Mincrosoft Update KB4103721.which can be downloaded from:

https://www.catalog.update.microsoft.com/Search.aspx?q=KB4103721