Here is quick guide of installing MTK6577 Usb drivers on PC Windows 7 x32 or x64 , MTK chip is also used in China Mobiles. I will provide you Guide for installation and Download for these drivers. As we know MediaTek uses VCOM Driver for fastboot and flashing china mobiles. This tested by SP Flash Tool.
Requirements : Download VCOM USB Driver for MTK 6577 China Mobiles.
Follow these steps.
Step # 1 : Open Device Manager in Windows. [Right Click on My Computer icon on Desktop then click on Manage after it click on Device Manager]
Step # 2 : Now Turn of MTK Device and Plug into Computer via USB cable. You will see MT65xx Preloader in Device Manager.
Note : If you not seeing this try removing battery from mobile and plug into computer without battery.
Step # 3 : Now double click on Installdriver.exe to run it, an popup appears to whether to install unsigned drivers or block, click on install it anyway. After it a confirmation dialog box will appear telling you Successfully installed usb drivers.
Note : This will only appear in Windows 7 are later.
Step # 4 : Restart your PC.
Step # 5 : After reboot open device manager again and wont turn on Mobile. Plug it into same usb port. Now MediaTek PreLoader USB VCOM port will appear in device manager.
Step # 6 : Now right click on it and click on Properties then select driver tab after it click on Update Driver. Click on Browse my computer for driver software.
Step # 7 : Now navigate to download folder and select Win7 folder.
Say Thanks if It Works