Horizon Not Working

Hi my horizon does not seem to work anymore, i have reinstalled it multiple times and restarted my PC multiple times. But it either just freezes or as it is constantly doing now it comes up with the error message “Horizon has stopped working”.
Below is all of the information that came within the error, any help would be aprreciated.

Description:
Stopped working

Problem signature:
Problem Event Name: CLR20r3
Problem Signature 01: horizon.exe
Problem Signature 02: 2.8.7.2
Problem Signature 03: 55f7a011
Problem Signature 04: Horizon
Problem Signature 05: 2.8.7.2
Problem Signature 06: 55f7a011
Problem Signature 07: 754
Problem Signature 08: 1a
Problem Signature 09: System.InvalidCastException
OS Version: 6.1.7601.2.1.0.256.48
Locale ID: 2057

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Hello deano try the download f r om my sig the one on main Page doesnt always work and make sure you have .netframework 4.0 for it to run