PMWall Troubleshooting
Common PMWall problems and how to clear them. Most live-event issues are one of three things: photos are not reaching the Cloud event, the wall is full and behaving as configured, or something is waiting in moderation.
The Mosaic Will Not Start
PMWall validates the event before starting and reports exactly what is wrong.
"No event is selected."
Select an event under Event Management on the Dashboard tab.
"The selected event folder does not exist."
The local event folder is missing. Click Sync Event to recreate it.
"settings.json was not found." or "settings.json could not be parsed."
The event has not been synced, or the sync did not complete. Click Sync Event and watch it finish. If it keeps failing, confirm the event has a PMWall template assigned in Foto Master Cloud.
"main.jpg is missing from the selected event."
The event has no main image. Upload one to the PMWall template in the Cloud, then sync again. If the template does have an image and you see a message about it not being downloadable, the event computer could not reach the image URL -- check connectivity.
"... settings are global. Remove the ... section from the event settings.json file."
The event's settings contain a section that belongs to the device, not the event: debug, printer, output, analysis, or advanced. These are device-level settings and are rejected in an event payload. Per-event engine overrides belong under engine instead. This indicates a template or backend problem rather than something to fix on site -- contact Foto Master support.
Contest Errors
If the event runs a contest, the mosaic will not start when the winning cells are wrong:
- Contest enabled with no winning cells -- shuffle the winning tiles in the Cloud template.
- A winning cell outside the grid -- the grid changed after the shuffle. Re-shuffle.
- Duplicate winning cells, or more winners than cells.
Fix these in the Contest tab of the template, then sync again. See Configuring PMWall Contest Mode.
Sync Is Blocked
"Stop the mosaic to sync event updates."
Syncing and running are mutually exclusive by design. PMWall cannot apply a new template to a wall that is already building. Click Stop Mosaic, sync, then start again.
A Warning About Clearing Placed Tiles
If a synced template changes Columns, Rows, Cell output size, or the main image on an event that already has tiles, PMWall lists what changed and warns that all placed tiles will be cleared on the next start.
Declining keeps the previous settings and changes nothing. Accept only if you genuinely intend to restart the wall from empty.
The Event List Is Empty or Stale
If the event list cannot be reached, PMWall shows locally cached events. Check the internet connection, that the account has access to the event, and that the license is active.
Photos Are Not Reaching the Wall
Work through this in order, using the Runtime tab's Runtime Stats.
- Is Raw Seen climbing? If not, photos are not arriving at all. The problem is upstream: check that the booths or Selfie Wi-Fi are online and pointed at the same Cloud event.
- Is Media Download empty? Open Queue Management and switch to Media Download. "No media queued for download" with a healthy connection means nothing is arriving in the Cloud gallery.
- Is Download Raw Photos enabled? Check Settings > Cloud. Without it, gallery photos never reach the mosaic.
- Are downloads failing? Sort by Status — failures first and use Retry Selected. Isolated failures on venue Wi-Fi are normal; widespread failures point at connectivity or the Cloud plan.
- Is anything waiting in moderation? If moderation is on, nothing is placed until approved. Switch the queue to Moderation and filter by Needs attention.
The Wall Stopped Filling
If Raw Seen keeps climbing but Accepted Placements does not, photos are arriving and being rejected. That is usually correct behaviour rather than a fault.
- Runtime State is frozen. The wall is full and the template's When the wall is full setting is Stop. This is the default. To keep placing late arrivals, change the setting to Keep everyone visible and restart the mosaic.
- The wall keeps replacing but few photos land. With Keep improving the match only, a photo is placed only when it beats the tile already there. Photos that improve nothing are skipped.
- Photos are duplicates. Near-identical photos are penalised. Duplicate relaxation only ever applies in Critical mode, and only when Allow duplicate relaxation is enabled.
The Event Is Running Out of Time
PMWall compares the time left against the cells left at your configured label rate. When projected capacity falls short, the event enters Critical mode; if the clock runs out first, it continues in Overtime.
If this happens regularly, the usual causes are a grid too large for the guest count, or a Labels Per Minute value in Settings > Printer that does not match the hardware. Use the Simulator tab in the Cloud template to size the grid before the event instead of discovering it during one.
PMWall Restarted Mid-Event
PMWall shows Restoring Previous Session and reports Recovered Tiles as it rebuilds from the tiles on disk.
Resume works only while the grid still matches. If Columns, Rows, or Cell output size changed, the previous state cannot be used and the placed tiles are cleared instead.
Printing Problems
- Nothing prints. Confirm Auto-Print Labels is on under Runtime Printing, and check the output mode in Settings > Printer.
- The C/R label is unreadable. Increase Label size or change Text color and Outline color in the template's Printing tab. The outline exists so the label survives over dark photos.
- Printing cannot keep up. Compare your real throughput against Labels Per Minute and correct it, so Critical mode warns you in time.
Printer settings and label options are re-read on every print pass, so these changes take effect without restarting.
The Virtual Mosaic Is Not Updating
- Confirm Upload Mosaic Tiles (Virtual Mosaic) is enabled in Settings > Cloud.
- Check Queue Management > Media Upload for failures, and retry them.
- Confirm the Virtual Mosaic add-on is active on the account. Without it the player reports that the add-on is required.
The High-Resolution Export Fails
Covered separately in High-Resolution Mosaic Not Generating or Not Compiling Properly.
Collecting Logs for Support
- Open Settings > Storage.
- Confirm Enable system log is on.
- Click Open Logs and collect the files.
Under Log Categories, enable the categories relevant to the problem -- Cloud and Network for sync issues, Licensing for activation issues, Storage for disk issues. Include the event name and roughly when the problem occurred.
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