BIM Coordinator Program (INT) April 22, 2024
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Installation & update
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Losing data in AC 22 - backup file has ending pln.t.c


Hello everyone.

My Archicad crashed and I lost my work from 4/7 although I worked the same file all last week and I have the autosave on. I have a temporary file with the ending pln.t.c 11/7 date which is perfect,  but the bup file and original pln file have 4/7 date

I changed the ending to this file to .pln but it cannot be opened. Any suggestions

Barry Kelly

Are you working in a 'cloud' folder by any chance?

If so it is recommended that you don't.


I can't say I have heard of a 'pln.t.c' file.

Was it located in the same job folder as the PLN and BPN files?

That is what makes me think you are working in a cloud storage folder.


Autosave file should appear automatically after a crash when you restart Archicad.

Just make sure after a crash you close all running Archicads first before re-starting.


The autosave files are stored in the autosave folder location as set in your Work Environment (your user file on a Windows system).

You will see a file with a decent file size and the date you want and it will have a '.fdb' extension.

Copy this out and rename it to '.PLN' and you can open it.

But there should be no need as this is what the autosave will open when you start Archicad.



One of the forum moderators.
Versions 6.5 to 27
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11

Adding to what Barry said, a file is a file that is created before the .pln is saved. If the save is successful .tc tag is removed and is replaced with the .pln file. 


If the .tc tag is still present then the save could of been interrupted which could be caused by the following:


  • If you're saving to an external storage device and the external storage is unplugged during the save process
  • Saving to a network server/file server and the connection is dropped causing an improper save
  • As Barry said saving to cloud storage solutions e.g. iCloud/Dropbox/ in which these applications if they're syncing other files can interrupt Archicad's saving process
  • And it may be caused by an Antivirus application which traps the .pln file if it's not known to the Antivirus application
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