Opening files with VR OW errors over UNC path

[HengiFettlich]

Describe the bug. What happened?

1. Create UNC share with CT.dcm
2. Open Weasis
3. Drag&Drop file via UNC path into Weasis Viewport (i.e. \Hostname\Share\CT.dcm)
4. Error message with log output

CT.dcm.zip

What version of Weasis are you running?

4.6.6

On which system the problem occurs?

Windows

Relevant log output

13.02.2026 13:36:27.525 *ERROR* [DicomModelLoader-1] org.weasis.dicom.codec.DicomMediaIO: Cannot read DICOM:java.lang.IllegalStateException: uri: file://Hostname/Share/CT.dcm?offset=2218&length=33536
	at org.dcm4che3.data.BulkData.getFile(BulkData.java:147)
	at org.dcm4che3.data.BulkData.openStream(BulkData.java:165)
	at org.dcm4che3.data.BulkData.toBytes(BulkData.java:193)

Additional contextual elements

Using dcmdump from dcm4che, dumping the file with UNC paths works normally. This seems like an edge case with unescaping the file URI.

[nroduit]

I cannot reproduce your issue. If you drag and drop from a network-share, it cannot work, see #353 (comment)

[HengiFettlich]

You are actually right, sorry! In the application I use it's possible to add foreign programs and pass arguments. What I did was add Weasis.exe as the program and the UNC path of the folder as the argument, making sure that the UNC path gets escaped.
Instead of: Weasis.exe \\Hostname\Share
Do: Weasis.exe \\\\Hostname\\Share.
This should be possible in CMD/Powershell too.
Usually this works fine, except when elements are present with VR OW, like Overlay Data.

Edit: Drag&Dropping the containing folder from the file share also causes the error.

[Spenhouet]

As I shared in #778 this issue also occurs for files stored in a WSL folders when Weasis is running on the Windows host. Then the path to the WSL folder/file is a UNC path which isn't properly loaded by org.dcm4che3.data.BulkData.getFile.

I opened an issue on dcm4che side as it probably should be addressed on their end: dcm4che/dcm4che#1562