Once you've downloaded the JPEGmini plug-in please follow these steps to install the JPEGmini plug-in into Lightroom:
1. Double click on the JPEGminiLightroomPlugin_126.96.36.199.exe or copy the file jpegmini.lrplugin to your hard drive
2. Open Lightroom and select File > Plug-in Manager
3. Click the "Add" button below the plug-in list
4. Locate the jpegmini.lrplugin on your hard drive, select it and click “Select Folder” (it should be under: Local Disk > Program Files (x86) > ICVT > JPEGminiLightroomPlugin)
To activate the license for your JPEGmini plug-in, perform the following steps:
1. In the Lightroom Plug-in Manager window, select "JPEGmini"
2. Enter your activation code in the field at the top of the Plug-in manager window
3. Click “Activate”
4. After a short wait the plug-in will be activated and the label will change to "Activated"