D5 Render Version: D5 Lite for Revit (Beta) v1.1.0.0001 / D5 Launcher 1.2.0.0120
Graphics Card: NVIDIA GeForce RTX 4070 Laptop GPU
Driver Version: 32.0.16.1088
Host Software: Revit 2025 and Revit 2027.2 (fails identically in both)
D5Lite_Bug.zip (35.3 KB)
Issue Description:
Screenshots/Videos Description: Clicking “Connect to D5 Lite” in Revit does nothing visible. The tooltip changes to “D5 Lite is running”, but no window ever appears. I checked all monitors, Alt+Tab, the taskbar and Task Manager, and there is no D5 Lite window anywhere. D5 Render and D5 Sync work perfectly on the same machine.
I searched the forum before posting and could not find this specific issue reported.
Root cause (from logs):
The engine process launches correctly from C:/ProgramData/D5 Lite Revit/Engine/D5Lite.exe, but D5LiteDump.exe (SessionGuard) fails to write its guard.ready file:
Log.ERROR: Json write error: failed to open file
In skr::JsonWriteResult::dump_error At …/SkrCore/json.hpp:641
Log.ERROR: [SessionGuard] event=session_file_publish phase=temp_write status=failed
kind=guard_ready
path=C:/Users/RafaMoscardóERRE/AppData/Roaming/d5lite/revit/dumps/sessions/…/guard.tmp
In write_json_atomically At …/d5_lite_dump/src/session_guard.cpp:326
The guard then exits with code 4, and Revit reports:
Log.ERROR: [SessionGuard] event=startup phase=ready_wait status=child_exited exit_code=4
Log.ERROR: [LiteInterfaceRuntime] [SessionGuard] strong ready barrier failed
Log.ERROR: [LiteHostLifecycle] event=start phase=app_session status=failed
Log.ERROR: failed to open editor through RPC: 0
Evidence this is a character-encoding bug, not a permissions issue:
- The target directory exists and I can manually create files in it, so it is not a permissions or antivirus issue.
- The D5 installer log shows the same path corrupted as “RafaMoscard?ERRE”, confirming the encoding is mishandled somewhere in the D5 codebase.
- My C:\Users\ folder contains a stray directory named “RafaMoscardóERRE”, created by a different application with the same class of bug (UTF-8 read as Latin-1). Screenshot attached. This is a known failure pattern for non-ASCII paths.
Why the installer workaround does not help:
Installing as “All Users” (engine correctly placed in C:/ProgramData/) does not fix it, because the session/dump directory is always under the user profile and is not configurable.
Steps to Reproduce (optional):
- Use a Windows account whose username contains a non-ASCII character (e.g. “ó”).
- Install D5 Lite for Revit.
- Open Revit and click “Connect to D5 Lite”.
- The tooltip shows “D5 Lite is running” but no window ever appears.
Request: Please make D5LiteDump.exe handle non-ASCII characters in user profile paths (wide-character / UTF-8 aware file APIs). This will affect any user whose Windows account name contains accented characters, which is very common in Spanish, French, Portuguese and other locales.
