C# (CSharp) Microsoft.Exchange.Clients.Owa.Core UserOptionPropertyValidationUtility.ValidateSignatureTextCallback - 1 examples found. These are the top rated real world C# (CSharp) examples of Microsoft.Exchange.Clients.Owa.Core.UserOptionPropertyValidationUtility.ValidateSignatureTextCallback extracted from open source projects. You can rate examples to help us improve the quality of examples.