Vanilla 1.1.9 is a product of Lussumo. More Information: Documentation, Community Support.
The problem probably was some corrupted file in your project. Not sure wich it was, but most of these origin from a corrupted index. Restoring a backup is durely the easiest way to fix it. Glad it helped for you.
These issues definitely have a solution. It would be great if you contacted us via email at support@the-soulmen.com so that we could go through this issue with you and find a solution. The error actually appears only when the project file has been corrupted and something cannot be found -- so this should not be the normal case.
This error message is printed whenever something could not have been loaded as expected. So for example if a document that is supposed to be there is actually gone, Ulysses will show the error. While this is nice, it's not really helpful. And you have to not just click this message away. Thus, we will change this in the next version:
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