WP-2641M-CE7 (WinCE7 Based) User Manual v 1.0.1 Page: 129
7.2.1.
SDK Updates for VB.NET or C#
You can just change the old one with a new one.
Step 1: Get the latest version of the PACNET.dll
The latest version of the PACNET. dll can be obtained from ICP DAS web site.
http://ftp.icpdas.com/pub/cd/winpac_imx6/WP-2641/sdk/pacnet/
Step 2: Copy the PACNET.dll file to PC and WP-2641M-CE7
The DLL files on PC are located at anywhere only the solution can reference it.
The DLL files on WP-2641M-CE7 are located at the same directory as the .exe file.