If you have tried to install Bookshelf on a Windows 7, 8, or 10 system and have received an Invalid Signature or Corrupt Installer error please follow these steps to install Bookshelf on your PC.
Download Bookshelf for Windows
Click on the Download button.
Save Installer to your computer
When prompted click the Save button. Once the Installer has been downloaded, click the Open Folder button to be taken to your download folder.
Run Installer as Administrator
Right click on the Bookshelfsetup.exe and choose Run as Administrator from the menu.
The installer will launch and from here you can install Bookshelf as you normally would, click here for instructions on installing Bookshelf, start at Step 2.