https://community.blueprism.com/t5/Product-Forum/Collection-fields-that-begin-with-a-space-throw-an-error-in-Blue/m-p/66419#M19024 For anyone who upgrades to 6.3.x and suddenly starts seeing issues with collection fields that didn't exist prior. The error you will receive is "The field 'StartsWithSpace' doesn't exist within this collection" but since the field name doesn't start with a space in the error message, it can be a little hard to debug.  This works without issue in 6.2 and earlier. Checking the help document says that fields cannot contain a dot or bracket, but no mention is made of spaces. This only appears to affect fields that begin with a space. Ending with a space or containing a space elsewhere works as expected in testing.  I have spoken to BP support and they have advised that it was an unintentional break in 6.3 and should be resolved in 6.4.1 expected to be released in mid-November.  Wed, 31 Oct 2018 19:34:00 GMT RodStewart 2018-10-31T19:34:00Z https://community.blueprism.com/t5/Product-Forum/Collection-fields-that-begin-with-a-space-throw-an-error-in-Blue/m-p/66419#M19024 For anyone who upgrades to 6.3.x and suddenly starts seeing issues with collection fields that didn't exist prior. The error you will receive is "The field 'StartsWithSpace' doesn't exist within this collection" but since the field name doesn't start with a space in the error message, it can be a little hard to debug.  This works without issue in 6.2 and earlier. Checking the help document says that fields cannot contain a dot or bracket, but no mention is made of spaces. This only appears to affect fields that begin with a space. Ending with a space or containing a space elsewhere works as expected in testing.  I have spoken to BP support and they have advised that it was an unintentional break in 6.3 and should be resolved in 6.4.1 expected to be released in mid-November.  Wed, 31 Oct 2018 19:34:00 GMT https://community.blueprism.com/t5/Product-Forum/Collection-fields-that-begin-with-a-space-throw-an-error-in-Blue/m-p/66419#M19024 RodStewart 2018-10-31T19:34:00Z https://community.blueprism.com/t5/Product-Forum/Collection-fields-that-begin-with-a-space-throw-an-error-in-Blue/m-p/66420#M19025 I had the same problem migrating an environment from v5.0.23 to v6.3.1, what I did was analyze the xml of the processes and objects looking for spaces with a search pattern. Directly from the Blue Prism bd. Thu, 08 Nov 2018 20:15:00 GMT https://community.blueprism.com/t5/Product-Forum/Collection-fields-that-begin-with-a-space-throw-an-error-in-Blue/m-p/66420#M19025 EstebanCarrasco 2018-11-08T20:15:00Z https://community.blueprism.com/t5/Product-Forum/Collection-fields-that-begin-with-a-space-throw-an-error-in-Blue/m-p/66421#M19026 Are you sure that its affecting only fields that are begginning with space? I am facing the same issue with field, that is ending with space... I am not able to pass the field into action stage. On BP V5 it had been working properly, on 6.3 we are receiving 'The field does not exists within collection' Thu, 22 Nov 2018 18:52:00 GMT https://community.blueprism.com/t5/Product-Forum/Collection-fields-that-begin-with-a-space-throw-an-error-in-Blue/m-p/66421#M19026 RostislavPelika 2018-11-22T18:52:00Z