I have been trying to install OSMC using the windows installer and the downloaded OSMC_TGT_rbp2_20150628.img.gz image. But it does not work. Either it fails during installation or if it shows success - the RPi 2 does not boot up.
But the same OSMC_TGT_rbp2_20150628.img when installed with Win32DiskImager it boot and works fine (except the wifi)
What’s wrong? 
If you upload the log this may help us. It can be found in C:\Users\YourUserName.
Sam
Thanks Sam for the quick reply!!
I can’t seem to upload the log file here… so here is the pastebin link
http://pastebin.com/dK2fT6TQ
Are you running the installer as admin? This is required.
Something has locked the volume. Perhaps an antivirus program, Windows Autoplay or something else.
Sam
But Win32DiskImager works fine…everytime!
I have turned off Antivirus also.
For whatever reason, the OSMC installer cannot lock your device. Win32DiskImager is not used in the OSMC installer. Maybe it has a better way of locking the device. I’m willing to bet this is something trivial though. Can you verify you’re not downloading and running the installer off of the SD card as well? Sometimes people make this mistake
Sam
The installer is on my laptop HDD.
Problem is, sometime the OSMC installer is successful but even then OSMC fail to boot up.
Very likely your antivirus is interfering with the imaging process. Try disabling your AV temporarily while running the installer.
FYI… I also could not the installer to work. I was using Win 10.
The error log (under C:\users<myLogin>) indicated the installer could not write to the MBR since the SD card was “locked.” Temporarily disabling Windows Defender did not help.
I finally resorted to using an old laptop running Win 7. It worked.
It’s working on Windows 10 here. Something must’ve been keeping the drive open.