[SOLVED] Unable to install modules

[Owens]

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The error message when i click on Extensions -> Modules is:
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Remote server or file not found

You tried to access the address http://www.mywebsite.com/admin/listmodu ... _=7b4ba190, which is currently unavailable. Please make sure that the web address (URL) is correctly spelled and punctuated, then try reloading the page.
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I did a fresh install of 1.9.3 and had this problem. The solution was to re-uploaded all the modules. That fixed the problem.