Trying to check in some code I kept on receiving this:

Unable to PUT new contents for ##some path##.  [403, #0]  
Could not prepare to write the file  [500, #200014]  
Base checksum mismatch on '##some file##'n   expected:  4a5d17918bddd2c52c396f9b604fb3e9n     actual:  b138c1fa977c20bd4898362ef1ab6558n  [500, #200014]  

Also, the checkin was extremely slow. Turns out I had to upgrade my local client of svn to 1.8.8 and upgrade the repository. Reloading IntelliJ was the final fix.