NPOI FontHeightInPoints Method Not Found Error: Troubleshooting Guide

The error you are experiencing is related to the NPOI library. It seems that you are trying to use the `set_FontHeightInPoints` method on the `IFont` interface, but it is not available. This error typically occurs when you are using an outdated version of the NPOI library or have a mismatch between different versions of the library. To resolve this issue, you can try the following steps: 1. Update the NPOI library to the latest version. You can do this by using a package manager like NuGet if you are using Visual Studio, or by manually downloading the latest version from the NPOI GitHub repository. 2. Make sure that all your NPOI dependencies are up to date and compatible with each other. This includes the `NPOI.SS.UserModel` package, as well as any other related NPOI packages that you are using. 3. Check your code for any references to the `set_FontHeightInPoints` method and make sure that you are using the correct method name and parameters. Double-check the documentation for the version of NPOI you are using to ensure that the method exists and is being used correctly. If you have followed these steps and are still encountering the error, please provide more information about your code and the specific version of NPOI you are using.