Alright so that’s not great. So for reference, I don’t recommend messing around the registry until other options are exhausted, even when we know the effects as other applications can have adverse effects. However, I’ll bring you the information regardless. If the error is correct and you indeed want to lift the path size cap, I’ve got some resources. However if the second line of the error is correct, there is an asset in your external actors folder (which comes from world partition) that’s pitching the illegal characters error that could be tossed to be able to open the project temporarily. However this has the possibility to cause errors in the level, so back up the project beforehand.
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Important staff response on the matter:
More step by step tutorial:
https://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles/The-Windows-10-default-path-length-limitation-MAX-PATH-is-256-characters.html