In my case, the download was around 150MB.

After it finishes discovering files, you’ll have to download a small amount of files.

This may take a few minutes to get through, but it’ll still be a lot faster than downloading everything from scratch.

If everything’s working properly, it should start “Discovering files”.

Start Uplay, and tell it to once again download Siege.

The name should be fairly straightforward, but I don’t have a screenshot since I’ve already previously deleted the folder.

Delete the Uplay download-in-progress folder, which is located in the Siege folder.

Delete the STATE file in the Uplay game directory (1KB file).

For example, my Uplay installation puts the game’s files in this location: You need to put Steam’s copy of the game files in the “actual” game location, not where Uplay’s download-in-progress is going on – these are two different locations, with the download-in-progress being located within the game’s “normal” location.

Copy the Siege game files from Steam into the folder where Uplay installs the game.

(You probably only need to get the directory itself made here, but better safe than sorry if you can wait the full minute) Navigate to the game’s location on Uplay and check that the files are indeed there (see step 3), then cancel the download. Pause the download a minute in, after the file structure has been created.

Start the Rainbow Six Siege download on Uplay.

If you’re reading this in the far future then this method may also become outdated and no longer work. Quick disclaimer: I can’t guarantee that this will work for you, but it worked for me. Perhaps you think that that’s silly, and would like a way to not have to download everything again. Perhaps Uplay asked you to re-download ~35GB of game files, refusing to use your existing game files from Steam (error validating files). Perhaps at the end of the Free Weekend you purchased the game outside of Steam, using your new key to activate the game on Uplay. Perhaps you found that you liked the game. Perhaps, like me, you decided to try out Rainbow Six Siege on Steam during a free weekend.

Ubisoft r6 download