When saving a C# TBB I recently had the error message ‘Error 1 Invalid URI: The format of the URI could not be determined.’?

My first thought was to check the URI in the AssemblyInfo.cs file – was it the correct folder URI?  Did I have a typo?  Did the folder exist?  But, all was fine.

Then I recalled seeing this error before and it is related to the config.xml file that we create using TcmUploadAssembly.exe to upload the TBB.  In this file we must specify the URL of the server, which is, of course, also a URI.

The wrong value was:  <targetURL>localhost</targetURL>

Correct:  <targetURL>http://localhost</targetURL>

So, just in case you ever hit this error I hope this little tip can save you some time.