Getting started with KMyMoney... I can successfully open and save a file that is on my local machine. However, if I try to use a file on a remote machine, I get the error, "Unable to open file '//sharename/file' for writing. C:\...\kmymoney\plugins\xml\xmlstorage.cpp:510".

I get the same error if I attempt to use the file on a linux server (via samba) or another windows machine (shared folder). I can read and write txt or MS Word files from the location, just not KMyMoney files.

What version of KMM are you running, and which OS?

KMM version 5.1.3-5b03a2216
Windows 11 Home, version 22H2

I should clarify my problem statement a little.

I can open the file from the remote file system. I get the error when I attempt to save the file. Interestingly, the backup file is successfully created (file.kmy.~6) on the remote file system when I attempt the save.

I know there used to be a problem saving remotely from a Windows system related to the actual system calls used, but I thought it had been fixed, although I don't remember exactly when. It appears your version is from August, 2022, so you might try getting a newer version to see if the problem is still present or not.

The version mvjohnboy is using should actually contain the fix ostroffjh is talking about. The source code location reported (xmlstorage.cpp, line 510) identifies, that KMyMoney is trying to write the data to a temporary file on the local disk. This is done first and if successful the file is copied to the remote location in a second step.

I found a work-around.

In windows explorer, I used "Map network drive..." to a assign a drive letter to the fileserver directory.
My_share_name(\\hostname) (S:)

When I opened my file navigating via the drive letter, I was able to successfully save it.

That error message you mentioned sounds frustrating. Have you tried checking the file permissions on the remote machine or server to make sure that KMyMoney has the necessary permissions to read and write the file? It's also possible that there may be a connection issue with the network or shared folder.