To upgrade an existing OPCAE.NET based application usually only the following steps are required:

1. Open the solution in Visual Studio
   
   
2. Remove the opcaenet.dll reference
   
   
3. In Visual Studio 2008 change the Target Framework in the project properties to   .Net Framework 3.5
   Older Visual Studio versions don't have this selection.
   In Visual Studio 2010/2012/2013/2015 the Target .Net Framework can be set to .Net Framework 4.x
   In this case the DLL version for .NET4 needs to be referenced (see below)
   
   
4. Add a reference to the OPCAE.NET V8.0 (or newer) assemblies:
   - OpcAeNetUA.dll    respectively    OpcAeNetWpfUA.dll
   - OpcNetBase.dll
   in the OPCAE.NET setup directory.
   
   For the .NET4 target platform the references must be set to the DLLs:
   - OpcAeNetUA.Net4.dll    respectively    OpcAeNetWpfUA.Net4.dll
   - OpcNetBase.Net4.dll
   
   
5. Add a reference to the OPCAE.NET UA Option assembly
   - OpcAeNetUaOption.dll or OpcAeNetUaOption.Net4.dll
   in the OPCAE.NET UA Option setup directory
   
   For the .NET 4.x target platform the reference must be set to the DLL:
   - OpcAeNetUaOption.Net4.dll
   
   
6. Rebuild the application. No code changes are required.
   
   
7. Use the UA Client Configuration Utility to create a default UA configuration.
   Drag the application EXE file to the utility shortcut or start the utility and browse to the application.
   In the main dialog click the  Create UA Configuration  button 
   
8. Edit the default configuration to define proper names and create a certificate for the application.
   To access remote UA servers:
   - the exported client certificate needs to be copied to the server machine and imported.
   - the exported server certificate needs to be copied from the server machine and imported.