WebMail Pro ASP.NET documentation

Troubleshooting issues with database

Issues when using MS SQL

If you use MS SQL, you may encounter the problem with MySQL.Data.dll missing in the system. That may happen, for instance, if you try to open the calendar. The file is required for the application to build and run successfully. It has to be found either in bin directory of the application, or as a part of MySQL installation on the server. For licensing reasons, however, we cannot ship the file as a part of the product.

If you don't have MySQL installed, you can download the archive containing MySQL.Data.dll file at:


and unpack it into bin directory of WebMail Pro. You may need to adjust WebMail.csproj file regarding MySQL library version:

<Reference Include="MySql.Data, Version=, Culture=neutral, PublicKeyToken=c5687fc88969c44d, processorArchitecture=MSIL">

Issues when using MySQL

Make sure you have ODBC Connector for MySQL installed:


Note that setting up version 3.51 is recommended, many of our users reported issues with version 5 and going back to v3 fixed those.