"unexpected file format" when opening file

After working all weekend on this model - it will no longer open, same is true with the backup file. Just get the “unexpected file format” message. Frustrating to lose so much hard work. Does anyone know if it’s possible to recover files in this situation? file is too big to upload, even when zipped. Hoping for a miracle.

Thanks for any help at all!

Don A.

Upload the file to a file sharing service like Drop Box and share the link. @colin has some magic tools that can help and he is usually able to recover the components and materials in the model at least.

Have you been saving your file to an internal drive or outside of the computer?

I always save to the internal hard drive. But will copy to external device if I want to work elsewhere. Hopefully the file can be downloaded with the following link.

Thank you DaveR and @colin for your attention.

Click here to download attachments.

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