Factorio Forums

I use several installs, one of them is for
a) creating /testing mod and
b) a project where a base builds its self (using Recursive Blueprints)

the data for the latter is only in the blueprint library because i have to restart all the time (to test it still works)
after returning to the project I found the blueprint library to be empty

i have not interacted with library since the issue appeared.
I still have something labeled "blueprint-storage.dat" I do not know if this is storing an empty list or if this has the original storage but is erroring on load.
is there a way to restore the old library or is it all gone?

If the size of blueprint-storage.dat is ~1kB then it's most likely empty. If there are blueprint-storage backup files in the directory you may try copying them over blueprint-storage.dat (assuming that one is empty, if not make sure to keep a backup of it!) Otherwise if you have a save you know you used your blueprint library in you can try recovering it from that save.

If you have Python3 installed you can try my Blueprint Decoder tool to decode the "blueprint-storage.dat" file into a JSON file and that into a standard blueprint string:
The "-s" option tells the tool to skip bad/unparsable blueprints. So lookout for lines with "ERROR" in the "x.err" file.

thank you Hornwitser. it was at ~1kB the 2nd suggestion worked, I got the blueprints back from my planning save.