Along with deleting the cache file were did you also try deleting the configuration folder as well? If the problem is due to an issue in here re-installing the product will not fix the problem and you would need to clear out this configuration folder. Please give this a try and let us know if the problem persists. If it does I can open a ticket for you so this issue can be looked into further.
Here are steps to delete the configuration for rename it so it can be recreated:
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