Microsoft Visual Studio Community (free) or any edition of Microsoft Visual Studio
Framework, web server, database, and tools you need to build and run websites and applications on the Microsoft Web Platform.
This package allows you to edit the entire web site application or just the ASP.net Resource Files to enter translation text.
ResXResource Manager (free) - is a free application that enables you to edit standard Microsoft .NET string resources from multiple different resource files together inside one single data grid.
This simplifies the translation of strings to multiple different languages by providing you a compact and effective overview of all languages of each string resources inside a single data grid.
Built-in automatic checks for missing translations and different number of string format placeholders helps you in increasing the quality of your translations.