let me ask you some questons first:
Which version of RapidMiner Studio (the standalone GUI client) do you use?
Which version of RapidMiner Server (the Server component, formerly called RapidAnalytics) do you use?
What exactly did you enter in the Remote Repository dialog (please don't post your actual password
Are there more information in the log (USER_HOME/.RapidMiner/rapidminer-studio.log) file?