after finally resolving the blank page issue by installing a new wordpress and importing only posts, comments and so on, I now have a very strange problem.
I noticed that the number of comments was very high - basically it was twice the number it should have been. I checked everything and noticed that every comment got duplicated. I deactivated all plugin and themes as usual, but comments still kept duplicating.
I emptied the database table (too many comments to delete) to import it again later, but comments keep duplicating! In the comments table, they are saved as pingback with comment agent "The Incutio XML-RPC PHP Library -- WordPress/3.3.2". Is there something I can do to solve this issue?