Configure TeamCity to build from SVN trunk, branches and/or tags
First, ensure your VCS root is the root of your SVN repository in your administration panel, instead of being pointed to the trunk directory.
Then, for each build configuration, edit the checkout rules in your VCS Configuration. Add the checkout rule you desire.
For example, for your 'trunk' build configuraton, you would have a checkout rule of: +:trunk => .
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If you have a tag or branch you want to build, just create a new build config with a corresponding checkout rule. A tag of 'release-1.1' would have a checkout rule of: +:tags/release-1.1 => .
Here is the documentation on checkout rules: http://confluence.jetbrains.net/display/TCD65/VCS+Checkout+Rules
I had similar problem with SVN in TeamCity and to allow work with multiple branches I used Configuration parameter to pass "branch" since TeamCity doesn't support multibranch for SVN.
And set trigger to start build from that branch:
So in project it looks like: