If you want to sign an assembly, you must have the source code, then you can sign it by creating .Net Module. 1. Create .NetModule CSC /out:<OutputModule.netmo... /t:module <CodeFile.cs> 2. Create a Keypair SN -k <KeyPairFile.snk> 3. Link Keypair with the assembly using Assembly Linker AL /out:<OutputAssembly.dll... <Module.netModule> /keyfile:<Keyfile.snk> There is a much simpler and easy way to do this, even if you do not have the source code. ILMerge is the ......