Try this first:
Download and install Bonjour Print Services for Windows.
Once installed, simply run Bonjour and it’ll detect and install the printer that’s connected to your Time Capsule.
If that doesn't work for some reason try this:
To setup a printer on a Windows 7 PC to a Mac shared printer:
- Install the printer locally first on the Windows PC, to make sure your PC has the proper print drivers on it.
- Connect to via USB cable to the Time Capsule. In the Devices and Printers folder, click on Add printer to begin the printer installation process
- Click on Add a local printer
- Pick Create a new port, and then choose Standard TCP/IP Port
- Enter the IP Address of your Time Capsule in the Hostname or IP address field (Note: Use the Airport Utility app – get it here – to find out the IP address used by your Time Capsule). Click Next
- Pick Custom and then Next
- Find your Printer in the list then click Next
- Give the printer a name, then decide whether to share it or not, and that’s it! You’re done.
