---
title: "OBS Studio — \"Error opening file: (null)\" After Windows Profile Rename"
domain: troubleshooting
category: streaming
tags: [obs, streaming, windows, lua, profile-migration]
status: published
created: 2026-05-14
updated: 2026-05-14
---

# OBS Studio — "Error opening file: (null)" After Windows Profile Rename

## Symptom

Loading a scene collection in OBS Studio triggers a popup like:

```
[<ScriptName>.lua] Error opening file: (null)
```

The `(null)` is the giveaway: OBS resolved the registered script path to nothing — the file doesn't exist where the scene collection says it does. Most commonly this happens after a Windows profile was renamed or migrated and `C:\Users\<old>\...` paths were not updated.

## Why it happens

OBS stores per-scene-collection Lua/Python script registrations inside the scene collection JSON at:

```
%APPDATA%\obs-studio\basic\scenes\<Collection>.json
```

Each entry under `modules.scripts-tool[]` is an absolute Windows path. Renaming the Windows profile does not rewrite these — the JSON keeps pointing at the old `C:\Users\<old>\...` location, and OBS surfaces the resolution failure as a `(null)` popup on collection load.

## Diagnose

From WSL (or any shell with access to `%APPDATA%`):

```bash
OBS_DIR="/mnt/c/Users/<current-windows-user>/AppData/Roaming/obs-studio"

# 1. List scene collections
ls "$OBS_DIR/basic/scenes/"

# 2. Find collections referencing the missing script
grep -l -i "<script-name-substring>" "$OBS_DIR/basic/scenes/"*.json

# 3. Dump the scripts-tool paths from each suspect collection
python3 -c "
import json, sys
d = json.load(open(sys.argv[1]))
for s in d.get('modules', {}).get('scripts-tool', []):
    print(s.get('path'))
" "$OBS_DIR/basic/scenes/<Collection>.json"
```

If a printed path contains `C:/Users/<old-username>/...` and the file doesn't exist on disk, you've found it.

## Fix

> [!warning] Close OBS first
> OBS rewrites the scene collection JSON when it exits. Any edit made while OBS is running will be overwritten. Confirm with `tasklist.exe | grep obs64` (WSL) or Task Manager.

### 1. Make the missing script reachable

Either:

- **Re-extract / restore the script** to a path under the new profile (recommended — gives you a clean canonical home), or
- **Leave it in the rescue/migration folder** and point OBS there (fragile if the rescue folder is later deleted).

### 2. Back up the scene collection JSON

```bash
SCENES="/mnt/c/Users/<current-windows-user>/AppData/Roaming/obs-studio/basic/scenes"
STAMP="$(date +%Y%m%d-%H%M%S)"
cp -p "$SCENES/<Collection>.json" "$SCENES/<Collection>.json.$STAMP.bak"
```

### 3. Rewrite the paths atomically

Edit the JSON in place by parsing it, replacing the matched path strings, and writing through a temp file (so a crash mid-write can't corrupt the collection):

```bash
python3 <<'PY'
import json, os
scenes  = "/mnt/c/Users/<current-windows-user>/AppData/Roaming/obs-studio/basic/scenes"
mapping = {
    "C:/Users/<old>/Pictures/.../<script>.lua":
    "C:/Users/<new>/Pictures/.../<script>.lua",
}
for fn in ("<Collection>.json",):
    path = os.path.join(scenes, fn)
    d = json.load(open(path))
    for entry in d.get("modules", {}).get("scripts-tool", []):
        if entry.get("path") in mapping:
            entry["path"] = mapping[entry["path"]]
    tmp = path + ".tmp"
    json.dump(d, open(tmp, "w"), indent=4)
    os.replace(tmp, path)
PY
```

OBS scene JSONs use forward slashes in Windows paths — preserve that style.

### 4. Verify

Re-run the diagnostic Python snippet and confirm every printed path resolves to a real file (translate `C:/` → `/mnt/c/` from WSL).

### 5. Reopen OBS

Load the scene collection. The popup should be gone.

## Why not just remove the script?

If the script is part of a third-party overlay pack (Twitch Pimpage, OWN3D, etc.), removing the registration also removes the overlay's source presets — fixing the path keeps the imported scenes intact. If you don't actually use the overlay anymore, removing the `scripts-tool` entry is fine; OBS will silently drop the broken reference on next save.

## Generalization

This same pattern applies to any OBS asset path stored in a scene collection or profile:

- Browser source local files
- Image / media source files
- Lua / Python script paths
- VST plugin paths

All of them are absolute, all of them survive a Windows profile rename in stale form, and all of them can be batch-rewritten with the same JSON-edit pattern above. Search for the old username substring across `%APPDATA%\obs-studio\` to catch them all in one pass.

## Related

- [[../../MajorInfrastructure/Devices/MajorRig|MajorRig device note]] — Incident Log 2026-05-14 (TTT/MLS scene popups) and 2026-05-07 (`majli` profile retirement that left these references stranded)
- [[../04-streaming/obs/obs-studio-setup-encoding|OBS Studio Setup and Encoding Settings]]