refreshed my pc to find my itunes has gone

If you have a question, then explain your issue in far greater detail than "haven problems downloadin it", and ask it.

See the further information area of Troubleshooting issues with iTunes for Windows updates for download advice and direct links. Review the rest of the tip for further advice if required.

If you wiped your library as part of this "refresh" then see Recover your iTunes library from your iPod or iOS device (or purchase history).

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