Can't login to dashboard – same old blank screen

I am new to wp. Have created a basic site last week which looked fine. Last night, trying to login to admin and it’s blank.
Last thing I had done last week was to activate wp-e-commerce version 3.8.7.6.2.
I can access the site itself, but not the admin.
Here is the list of things so far done:
– Refresh and logging through wp-login.php didn’t work.
– Through ftp, downloaded wp-config.php, opened with wordpad, deleted an extra space at the end and uploaded. But doing that I was unable to access the site itself either. Renamed it back to original and can access the site now. Repeated it once more with same results.
– Renamed wp-e-commerce plugin, didn’t fix. Renamed the whole plugin directory and didn’t fix.

Appreciate any help!