Default Mediatek 6572 driver issue[please solve this problem]

yesterday i have read the tutorial about backuping boot and recovery image of Mediatek mobile with sptool, so i have downloaded all the requirements of it and done the same that i saw in tutorial but problem is that my mobile is not detecting on sptool in off condition condition....
and then i thought that it may be problem with Mediatek driver but i don't know how to install Mediatek USB driver for my mobile((Micromax canvas fun a63-MTK 6572))).... please tell me how to install it...
i have found three .dll files in this drivers pack but i don't know what to do.......


sorry for my bad English and please don't avoid me and please please help Me