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The Subversion server acts as a repository for web pages when integrated with Contribute. All versions of published pages along with information such as their version number, date, author, and comments can be retrieved from the server.If you are an administrator, you can enable Subversion at the time of connecting to a non-administered website, or while administering it. The connection key for Subversion enabled website contains the Subversion server information. If you enable Subversion after the connection keys are distributed, resend the connection key to the users to get connected to the website.
You need to check the configuration of Contribute for SVN. Please check the workflow which you are using to configure SVN. you may check the links given below for this purpose.
I'm well aware of what SVN is and how to use it and if you'd actually read my post you'd realize I've seen both of the pages you'd linked and found them worthless for troubleshooting the issue as the provide zero troubleshooting information, only how to set it up.
As far as further information, in again testing this the dialog box has decided to sometimes spit out an error message that may be useful in getting to the root of the problem:
The error messages were produced by navigating to a page, clicking edit page, making an edit on the page and clicking publish.
I agree that we often receive such queries for Adobe Contribute. The above links which I provided is just for reference purpose to make sure that you are following the right workflow. It seems to be an issue with permission either on Subversion repository or FTP site. Could you please provide me some more information related to this issue.
Do you have any firewall settings applied to your SVN?
Are you the administrator of the site which you are using in this workflow?
Which model you are using in Subversion repository. (lock-modify-unlock) http://svnbook.red-bean.com/en/1.6/svn-book.html#svn.advanced.locking.lock-communication
I do own and admin the site, but I don't own or admin the SVN repository. I'm sure there is a firewall on it but all appropriate ports have been opened as this is a university wide service inside our institution. I've also used an external third party SVN provider (http://beanstalkapp.com) and had the same results as mentioned above. I can confirm SVN working properly as I use it regularly via SVN specific clients, the unix command line and via the application I use for the majority of my code (not Dreamweaver). I haven't tested Dreamweaver beyond setting up a site according to Adobe's instructions and ran into similar problems as I did with Contribute.
We use the copy-modify-merge model for our development otherwise. In the case of all of my Contribute testing my client was the only one editing or modifying files on a brand new isolated repositories so there wouldn't be any conflicts with our normal development. As I said in my first post, if I try to publish a file I'll get a warning as posted above, but clicking publish a second time successfully publishes the file and commits it to SVN.