KeePass, WebDAV and Windows11 - saving not possible anymore.

[Michael]

please, can anyone help?

After switching from Win10 to Win11, KeePass refuses to save on webdav. When trying to save, it blocks until timeout, then tells something like "file may be corrupt...".

The WevDAV URL is like https://myserver.com:2078/myfile.kdbx
(accessing with user & password)

Loading is no problem, but the writing fails. Checking the server, a 0kb myfile.kdbx.tmp file was created. On Win10, everything works fine, it's just Win11 (so the webdav can't be the problem). Tested on 3 different Win11 computers in different networks, always the same issue. Double checked on a Win10 machine again, writing is no problem.

Connecting the WebDAV directly under windows (as a drive letter) works: i can read and write this "local" kdbx file (this is my workaround for now). So it MUST be a issue with KeePass.

Exceptions in the Win11 firewall for KeePass application and for port 2078 didn't help. Even disableing all firewall services wasn't helpful. I've also tried to disable the "file transaction" option in advanced settings. No effect, too. Now i'm absolutely out of ideas :-(((

[Paul]

Or you have set KeePass on the W10 machine to not use file transactions?
Tools > Options > Advanced, File Input/Output Connections, Use file transactions...

cheers, Paul

[Michael]

nope, Paul, all W10 settings are default. Tried to play with this option on win11, but didn't work.

[Paul]

Then it may be a change in .NET on the W11 machines.
What versions do you have?
https://www.askwoody.com/forums/topic/net-5-0-is-vulnerable-and-no-security-updates-are-provided-by-the-vendor/#post-2817395

cheers, Paul

[Michael]

`
dotnet --info

Host:
Version: 9.0.3
Architecture: x64
Commit: 831d23e561
RID: win-x64

.NET SDKs installed:
No SDKs were found.

.NET runtimes installed:
Microsoft.AspNetCore.App 8.0.16 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.16 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.3 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.16 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.3 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
None

Environment variables:
Not set
`

[Michael]

mhhh... looks there is no 5 there

[Michael]

anyway, thanks a lot for your support, Paul

[Dominik Reichl]

It could be due to the TLS support. Windows 11 supports TLS 1.3, whereas Windows 10 does not (it supports 1.2 at most). Maybe Windows 11 and your server don't like each other via TLS 1.3.

If you know how to work with the Windows registry, you could disable TLS 1.3 for testing:
https://learn.microsoft.com/en-us/dotnet/framework/network-programming/tls#configure-schannel-protocols-in-the-windows-registry

Best regards,
Dominik

[Michael]

Thanks Dominik,

i gave that try, but wasn't successful. (made a TLS 1.3 key and set a zero DWORD for Server and Client, then restarted windows).

Well, i've expected this result, because integrating the WebDAV URLs as drive letters and file reading/writing directly in Windows works. The error only occurs when KeePass itself wants to write to the URL.

best,
Michael