I also had this issue, but have now fixed it. Effectively, I uninstalled Subclipse and SVNKit and reinstalled an older version.
For reference: I was unable to update because it said I already had a newer version. I initially got the following error "library version must be at least 1.8.0, but is only 1.7.8 (r1419691)". I did not have the "SVN Interface" option in Preferences|Team|SVN. It also errored showing me an error saying that "An error has occurred when creating this preference page."
I used the info on the following site:
http://stackoverflow.com/questions/9303 ... n-headache. The answer by @matthewb provided step-by-step directions, which I took from and uninstalled/reinstalled Subclipse and SVN. Seems silly not to have already tried this. Here's a short version:
Remove Subclipse 1.8
(I had version 1.10, but same premise) - In Eclipse, under the help menu, choose Install New Software. Near the bottom, on the right hand side, click the link "What is already installed?" Near the top, you should see CollabNet Merge Client, version 3.0.x, or something similar (I think this is installed with Subclipse 1.8 ), click uninstall and follow the steps to uninstall. (Eclipse will then ask you to restart, click not now. ) Scroll down to the bottom, if you see Subclipse, version 1.8.x, click uninstall and follow the steps. Again, click "not now" when eclipse asks to restart.
(I also removed anything other remaining items referencing Subclipse or SVN)Download Subclipse 1.6.
(I used the Subclipse 1.8.x Update Site, which was already in the list, url: http://subclipse.tigris.org/update_1.8.x) You should still be in the Install New Software window. Near the top, where is says Work with: paste in
http://subclipse.tigris.org/update_1.6.x, download all the files (you may not need these, but I downloaded them all to be safe). Again, eclipse will ask you to restart, hit not now, and close down eclipse instead.