SVN Error: "' 'x' isn't in the same repository as 'y' " during merge

The problem lies in the fact the checkout information is different from what you specify in the svn merge command. Typically, it can be either:

• the hostname is different when you did the checkout. You did the checkout as from svn.example.com but now you are merging by referring to an host alias, like svn-alias.example.com. note that even the case is important. You can get this error if you do svn merge from SVN.EXAMPLE.COM. More on this here and here.
• the protocol is different from what you used for the checkout. E.g. http://svn.example.com versus https://svn.example.com Make sure you use the same protocol.
• you are specifying a username at svn merge in the form [email protected]. Try to remove the user@ specification (the user is passed anyway). svn considers the hostname, and thus the repo, different if you specify the user, even if the user is technically the same.

this is very much case sensitive. Sometimes if you right click in any branch and click merge https://mysite.com/svn/MYREPO/trunk as merge from . But my branch name has small letters for myrepo https://mysite.com/svn/myrepo/branches/mybranch. this cause me error surely check the case sensitivenes.. If its not matching type in the wizard correctly