Ok I'm really interested to find out whats going on with this one. I've been thru the entire internet. (no really ;) ). Basically we are creating upgrade packages for some solutions and these new packages contain exactly the same attributes as the pre-existing packages. But they fail, either using maintain or overwrite customizations.
It flags an error, on one attribute, that the optionset schema name is not unique. When you remove that attribute, it then simply fails with no error messages (getting to the String Maps part of the process, and then not carrying on any further.)
So, I can rule out that the schema names are different, or that the attribute types are different (they are exactly the same in both the original solution and the update solution)
The only other thing to note, is that the attributes it's potentially trying to overwrite, (or not as the case maybe when using maintain customizations) do contain data.
All the solutions are managed, any thoughts are appreciated!
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