Merging from branch to trunk.

I am trying to get the basics of branch management down, and have run into a weird issue.  I created a branch from the trunk.  I then attempted to do Merge -> Reintegrate a branch in the trunk after performing the necessary commit/updates.  The From URL was the branch folder I created previously.  I have tried this with a depth of Working Copy and Full Recursive, and the following issue always occurs.  

In TortoiseSVN, I saw conflicts on two files in the folder.  When I looked at the log, the message was "The last merge operation tried to add the file 'Foo.txt', but it was already added locally."  How do I resolve this issue?  The error occurs for a file I have not modified and for a file I have modified in the branch.  

Thanks!