firstly am new in using oracle...unfortunately i went wrong in installing oracle 11g...i has selected C:\ drive as the path mistakenly as in below picture 
i don't understand what happened but am getting a message unable to access my C:\ drive showing drive as below
and can't open programs like cmd(command prompt),systemRestore please help me in this....can i resolve this without installing the OS again....and can i do that by re-installing OS...
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