XAML is corrupt if you change an argument name too many times?

I am new to UIPath, but I’ve already seen this issue a number of times. The exact error varies, but it seems in each case that if you change the name of an argument a number of times, particularly if you change the name of a argument rapidly, the xaml gets corrupted.

  1. I created an argument in a library xaml called “out_boolSuccess”.
  2. I published the library a number of times and used it in an automation project.
  3. In the library project I was debating on the best way to return a boolean that indicates an exception occurred and I changed the name of the argument 4 or 5 times.
  4. When I try to publish the library, I get the error:

The assembly compilation returned the following errors:
‘ProcessIsRunning’ does not contain a definition for ‘out_boolSuccess’


  1. The xaml no longer contains any instance of the argument “out_boolSuccess”. I’ve even searched the xaml file’s XML and could not find it.
  2. When I test the xaml by choosing Run File, there is no error.

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The error message does not point to the real issue. When publishing the library, I had a test xaml using the old parameter name calling the xaml with the changed parameter name. This produced the same error message (not corrupt).

Check if ProcessisRunning is called from within the lib with a parameter of out_bootSuccess. By opening the xaml making the call, the parameter list (orange) will be updated to the current parameters. Save and error goes away.

Another way to see the real problem is to copy ProcessisRunning to ProcessisRunning2, then delete ProcessisRunning. There error will reported will reflect the xaml that has the bad parameter reference to ProcessisRunning.