[GNC] Gnucash suddenly cannot open the data file from Onedrive

[John Ralls]

> On Jan 4, 2026, at 18:33, Mike Brady <mrecky.101 at gmail.com> wrote:
> 
> I have identical folders for Gnucash files on a local disk and Onedrive. Opens fine from local. But attempting to open from Onedrive (for testing, files marked to always be available on the computer, so they should be identical in access time to the main files on the local disk; they don't take up a lot of space so I may leave it that way on the laptop if I can get Gnucash to open them again) produces "Unknown I/O Error (1002)" from Gnucash 5.14. Literally, it was working yesterday. It occurs no matter how I try to open the file - double click from File Explorer, or open from within Gnucash. And, if I copy the files back to a new folder on a local drive, it works fine. So what's the story here? I don't recall seeing any updates to Onedrive in the last day or so, and have been using 5.14 successfully with Onedrive for several weeks otherwise.
> 
> Note1: my accounts on both the local machine and at Onedrive are listed as having "Full Control" for the .gnucash file.
> Note2: this occurs for ALL .gnucash files in Onedrive, not just my main one. So the running incremental backups GC makes are also inaccessible with the same error code. Files for other applications open and save normally using Onedrive.
> 
> Is there a list of Gnucash errors in the docs somewhere? I did some light searching and didn't find anything.
> 
> The only current workaround seems to be to manually copy the Onedrive folder to a local disk outside of the backup system tied to Onedrive and work there, then manually copy everything back when done so the other computer can download it. File copies in File Explorer work normally, no errors.
> 
> Windows 11, desktop & laptop

Mike,

No, there’s no list of GnuCash error codes because we don’t use error codes that way and when we pop a dialog box with an error it has a description of what went wrong. Most other errors are logged in the trace file (see https://wiki.gnucash.org/wiki/Tracefile).

Microsoft Windows on the other hand is infamous for popping error dialogs like that. Google suggests that it’s a connectivity problem with OneDrive. GnuCash file handling is pretty basic: Give it a path and it will try to open the file with the standard C function fopen. If the operating system needs more than that for any particular remote/cloud file access then GnuCash can’t do it.

Regards,
John Ralls