Why cloud-synced folders cause freezes, save failures, and damaged project files - and how to work safely
A FireCAD project is not a single document. The project file (.atpx or .atp) is a live database that FireCAD writes to constantly - every time you connect a device, run an Auto Polyline, edit entity properties, or save. Cloud sync clients such as OneDrive, Dropbox, Google Drive, SharePoint, and Box are built for documents that change occasionally, so they react to each of those writes by locking the file and uploading it.
The result is a set of problems that look unrelated but share one cause:
| What you see | What is actually happening |
|---|---|
| FireCAD freezes for 20 seconds to 2 minutes on ordinary actions (Auto Polyline, Esc out of a tool, editing entity properties) | FireCAD is waiting for the sync client to release the project file |
| "The process cannot access the file because it is being used by another process" when saving | Sync locked the project file mid-save |
| Your last save is missing when you reopen the job | The save could not complete; FireCAD preserved your data to a temporary file instead |
| A project will not open, or reports a damaged or unreadable file | Sync captured the file half-written, leaving an incomplete file |
| Two people open the same project and changes vanish | Sync resolved a conflict by overwriting one copy |
None of these mean your work is lost, and none of them are caused by a defect in FireCAD. They are all sync interference.
The recommended way to work
Keep the working copy of a project on a local drive. Use the cloud for finished revisions and sharing.
- Create a local working folder, for example C:\FireCAD Projects. It must be a real local path, not a mapped or synced one.
- Copy the entire project folder there from the cloud location, then open the project from the local copy.
- Do your design work locally.
- When you reach a stopping point, copy the whole project folder back to OneDrive or Dropbox as a revision.
This gives you the speed and reliability of local work plus a cloud copy that is safe to share, because it is only written when you are not working in it.
If you need help copying a project correctly, see What Is the Best Way to Make a Project Revision or Backup the Project and Drawing? - the short version is to copy the entire folder and rename only the copied folder.
If the project must stay in a synced folder
Sometimes company policy puts all job files in OneDrive. In that case, stop the sync client from touching the project while you have it open. Any one of these works:
Option 1 - Pause syncing while you work (easiest)
- Click the OneDrive cloud icon in the Windows notification area.
- Choose the gear / Help & Settings menu, then Pause syncing, and pick a duration (2, 8, or 24 hours).
- Work in FireCAD, then resume syncing when you are done for the day.
Dropbox has the same feature under its tray icon, listed as Pause syncing.
Option 2 - Exit the sync client entirely for the session
- Click the OneDrive cloud icon, open the Help & Settings menu, and choose Quit OneDrive (Close Dropbox in Dropbox).
- Nothing syncs until you start it again, which gives you the cleanest run.
- Start it again after you close FireCAD so your work uploads.
Option 3 - Exclude the project folder from syncing
- In OneDrive settings, open the Account tab and choose Choose folders, then clear the checkbox for your FireCAD job folders.
- In Dropbox, use Selective Sync and clear the same folders.
- Those folders then stay local only, which is exactly what you want for active jobs.
Also turn off Files On-Demand for FireCAD folders. In OneDrive settings, under Settings or Sync and back up / Advanced settings, look for Files On-Demand and mark your FireCAD folders Always keep on this device. If a project file is online-only, FireCAD has to download it before it can read it, which produces the same delays.
Recovering a project that was already damaged
If a project will not open or a save was lost after sync interference:
- Do not keep working in the affected copy.
- Look for backups in the project folder's backups subfolder - FireCAD writes timestamped copies there.
- If a save failed, FireCAD may have preserved your data in a temporary file named like amts_save_xxxxxxx.atpx. Check your Windows temp folder (type %TEMP% into the Explorer address bar) and sort by date.
- Check the cloud provider's own version history. OneDrive and Dropbox both keep previous versions of a file, and the version from before the failed save is often intact.
- If none of that recovers the job, contact support and send the project folder. We can usually repair the project file and restore the connections.
Quick checklist
- Working copy on a local drive - not OneDrive, Dropbox, or a mapped network drive.
- If it must be synced, pause or exit the sync client while FireCAD is open.
- FireCAD folders set to Always keep on this device, never online-only.
- Copy the whole project folder for revisions, and rename only the copied folder.
- Never have the same project open on two machines at once.
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