The H series of errors are usually related to installation or hosting setup issues. If you are getting QuickBooks error H505 error on your device, it might be due to the fact that the computer on which you are trying to access your QB data requires additional setup. The QuickBooks error code H505 occurs when you try to access your QB data or company files on a computer that does not have a proper establishment setup. To fix the error H505 you should check your hosting and services first. You can also use the QuickBooks File Doctor tool to troubleshoot the error easily.