The steps are as follows:
1. Download
http://download.microsoft.com/download/e/f/b/efb39198-7c59-4ace-a5c4-8f0f88e00d34/vb6mousewheel.exe
This is a self-extracting package, which contains VB6IDEMouseWheelAddin.dll and its source program. Just unzip it to the desktop.
2. Choose to use VB6IDEMouseWheelAddin.dll directly, or compile the source program to create a new VB6IDEMouseWheelAddin.dll.
3. Run in cmd: regsvr32 VB6IDEMouseWheelAddin.dll. Before running, please switch the current path (cd command) to the desktop, or copy this dll to the default path of cmd.
4. Run "VBA Mouse Wheel Fix.reg" in the directory.
5. Run VB6.0.
6. Click Add-ins (A) in the menu => Add-in Manager (A).
7. In the list, select "MouseWheel Fix" and check the first two items in the loading behavior in the lower right corner of the "Add-in Manager", namely Load at startup (S) and Load/Unload (L).
8. Confirm and exit VB6.0.
9. Restart VB6.0, enter the code editing window, and the mouse wheel is supported successfully!