I am currently having a similar issue to this answers page https://answers.laserfiche.com/questions/83893/file-inputoutput-error-9004. I have checked the service account that is being used by the server has access to the folders in question. The storage is a NAS drive. This drive currently has a shared folder that volumes can be created on. The customer created another shared folder in order to create another set of volumes for another department. I am currently receiving the error in the title. I have checked security for both the non-working and working folder on the NAS. Would there be anything else to look at besides the service account and security settings for the folders?