Click or drag to resize

Evaluation and Licensing

GemBox.Email works in three different modes:

  • Free mode - free of charge, limited to 50 sent or received messages and message attachments up to 50 KB.

  • Time Limited mode - free of charge, limited to 30 days.

  • Professional mode - requires purchasing a license key, no limitations.

All modes use the same GemBox.Email DLL so there is no need to reinstall the component when switching modes.

The first thing to do when coding with GemBox.Email is to instruct the component in which mode it will be used. This is accomplished by calling ComponentInfoSetLicense(String) method with the specific license key parameter:

  • FREE-LIMITED-KEY, to use the component in Free mode.

  • The temporary license key that you receive after sending us a request for Time Limited mode.

  • The professional license key that you receive after purchasing GemBox.Email, to use the component in Professional mode.

Important note Important

ComponentInfo.SetLicense method must be called before using any other class from GemBox.Email component.

Tip Tip

ComponentInfo.SetLicense method can be called multiple times. What is important is that it is called with the same license key.

Ideally, it should be called at the startup of your application. For example, it can be called in a Main method, an application startup event or a static constructor of your main class.


You can evaluate GemBox.Spreadsheet free of charge and for an unlimited time period, just download the component, install it and use it in Free mode.

Free mode delivers the same performance and set of features as Professional mode, with the following limitations:


If you have evaluated the component and are satisfied with it, you can purchase the license key to use the component in the Professional mode - without any limitations.

After purchase, the only thing you need to do is to replace FREE-LIMITED-KEY with your purchased license key in ComponentInfoSetLicense(String) method call.

Note Note

There is no other installer or DLL for the Professional mode. You should continue to use the reference to existing GemBox.Email DLL in your project when switching to Professional mode.

Professional mode also includes technical support with prompt bug fixes. For more information, see Technical Support.