Troubleshoot
Find the message you see, then do what the table says. Messages appear in the installer’s window, in REAPER’s console, or in the line at the top of the panel. Click that line to see recent messages.
When something isn’t covered here, run the check and read the log.
The installer
Section titled “The installer”| Message | Do this |
|---|---|
| REAPER resource path not found … Start REAPER once, or pass –reaper-resource PATH. | Open REAPER once and close it, then run the installer again. For a portable REAPER, add --reaper-resource and its folder. |
| PresTools needs a Mac with Apple Silicon (M1 or later); this one has an Intel processor | PresTools 0.1.0 doesn’t run on Intel Macs. PresTools’ next release installs on them, with the tools on the CPU. |
| PresTools needs 64-bit Windows on an x64 processor | Windows on Arm is not supported. |
| Could not download uv (check the internet connection) | Check the connection, then run the installer again. |
| Run this from the unpacked PresTools package | Unzip the package first, and run the installer from inside the unzipped PresTools folder. |
| could not replace reaper_prestools…; close REAPER and run the installer again | Quit REAPER, then run the installer again. |
| the panel’s web view is missing libraries (Linux) | Install WebKitGTK 4.1, as the installer’s next line says. |
| AMD does not list the … for PyTorch on Windows, so the tools will run on the CPU. | Your AMD GPU isn’t one AMD’s PyTorch supports. The tools work on the CPU. --torch-backend rocm tries AMD’s build anyway. |
| the shared libraries did not install; no tool will work | Check the connection and free disk space, then run the installer again. |
| … feature(s) not ready. Re-run the installer, or run the check with –verbose for details. | Run the installer again: it repairs only what is missing. If a line still says FAIL, run --check --verbose and read the error. |
| no environment at … Run the installer first. | --check and --smoke need a finished install. Run the installer without them first. |
If Windows shows Windows protected your PC, click More info, then Run anyway.
If nothing else helps, --force-venvs rebuilds PresTools’ Python environment from scratch and puts back your components.
The panel
Section titled “The panel”| What you see | Do this |
|---|---|
| There is no action PresTools: Show panel. | Restart REAPER after installing. If it still isn’t there, check that the extension is in REAPER’s UserPlugins folder, and run the installer again. |
| PresTools: the Python environment is missing. Run the installer. | Run the installer again. |
| PresTools: interface not found in … Re-run the installer. | Run the installer again. |
| The panel stays blank, and after 15 seconds: PresTools: the web view did not start. (Windows) | Install the Microsoft Edge WebView2 Runtime, then reopen the panel. |
| PresTools: the web view did not start; see logs/extension.log (macOS, Linux) | Read the log. On Linux, check that WebKitGTK 4.1 is installed. |
| PresTools: the system web view is unavailable. | On Linux, install WebKitGTK 4.1. Elsewhere, read the log. |
| the PresTools core could not be started; see logs/extension.log | Run the installer again, then --check. |
| the PresTools core is not responding or the PresTools core stopped unexpectedly | Try again: the next request starts it again. If it keeps happening, read the log. |
The tools
Section titled “The tools”| Message | Do this |
|---|---|
| … is not installed yet. Install it in Settings, under Components. | Click Install on the page, or add it in Settings → Components. |
| could not install: … | Adding a component failed; the rest of the message is the reason. Check the connection, then click Install again. |
| the prebuilt wheels are missing from … | Run the PresTools installer again, then add Beat detection again. |
| Select an audio item first: what this writes goes where the item sits. | Select the song’s audio item in the project. |
| no beats were found in this audio | Select an item with a beat, such as the full mix. |
| The beats come out at double or half the tempo. | Use Halve or Double, or set Min BPM and Max BPM in the detection settings and detect again. |
| A marker cannot be read | A marker’s instruction is wrong, such as [5/9]; the message says what is wrong. Fix or delete that marker. |
| The chords don’t sit on the bars. | Map the tempo first, then find the chords again with Snap to grid on. |
| Line …: under the chord chart | That line of the chart has a mistake. Fix it before Apply chart. |
| No singing found in this item: select its vocal stem. | Select the vocal stem, not the mix or another stem. |
| there are no lyrics to align; write or recognize them first | Type the words into the editor, or click Recognize first. |
| The words come back in the wrong language. | Choose the language instead of Detect language, and recognize again. |
| … is not in a project; tick Multi-project to give each file one | A workflow with tempo, chord, or lyrics steps needs a project. Tick Multi-project, or add the song to the project and select its item. |
| … returned only silence on … | The model gave silence on that device. Try again with Use the GPU off in Settings, or another model. |
| The progress says … failed; on the CPU. | The GPU couldn’t run that model, so it finishes on the CPU. That separation model goes straight to the CPU for the rest of the session. |
| Stems were written but are not in the project. | The project was closed before the run finished. The stems are beside the song; drag them in. |
The GPU
Section titled “The GPU”Settings says No GPU: everything runs on the CPU when PresTools finds no GPU it can use. Hover over it for the reason.
- NVIDIA: install NVIDIA’s driver, then run the PresTools installer again. It replaces the CPU build of PyTorch with the CUDA build.
- AMD on Windows: only the GPUs listed under Graphics card (GPU) are used, with AMD Software 26.2.2 or later.
- Intel GPUs are not used.
Read the log
Section titled “Read the log”PresTools writes its log to Scripts/PresTools/Scripts/logs/extension.log, in REAPER’s resource folder. REAPER starts a new log each session, so read it before you restart REAPER. In REAPER, Options → Show REAPER resource path in explorer/finder opens the resource folder.
The smoke test (--smoke) also saves logs/smoke-report.json in the same Scripts/PresTools/Scripts folder.
In PresTools’ next release, the log moves to Scripts/PresTools/data/logs/extension.log.
To report a problem, use the feedback form and include the log.