We are aware of an issue which is affecting some PC players, which may cause a loss in progression. Borderlands 2 for PC saves in two locations, it saves your progression locally on your PC, and if you are connected to the internet, it will create a back-up cloud save through Steam. In most situation, the cloud save functions as a back-up, and can allow you to regain your progress in the event of either a loss of data on your system, or if you want to play the game on a second system with the same save file.
In most cases, this should work to protect your save data, but in some circumstances, can cause the opposite. The cloud version of a player's save file can fall behind the progress of the local file if the player either loses connection briefly, or is playing in offline mode. Should the Cloud Save fall behind the Local Save, the next time the game is launched, Steam will ask which version the player wants to use.
Should you receive this option, be very careful about which choice you select, as the selected file will overwrite (delete) the other file.
In most cases, it you are playing on one system, if Steam prompts you with the choice, usually the local file is further progressed than the cloud save. In this case, you will want to choose "UPLOAD" (use local saves), in order to copy your local file up to the Steam server.
In cases where you choose to play from a second machine, and the Cloud save is more progressed, choose "DOWNLOAD" (Use Steam Cloud Saves)to pull the file off of the cloud server and load it locally. Should a local file become lost for any reason, the same process should rebuild the lost data.
Players are advised to pay close attention when they upload to the cloud and download from the cloud. When they download from the cloud, the cloud save will overwrite and possibly cause data loss if the information on the cloud is earlier than that on their PC.
If you are unsure of which file is further progressed, you can switch Steam to Offline Mode when getting the "Do you want to use Cloud or Local saves?" box when launching the game. Once launching the game in Offline mode, you can see which saves are stored locally. If those are the most recent saves, you should select the "Use Local Saves" when they connect to Steam. If the saves you see while in Offline Mode are not up to date, you should use the "Use Steam Cloud Saves" when you reconnect to Steam.
Alternatively, you can disable Steam Cloud for Borderlands 2 and use local files only. To disable Steam Cloud support:
1) In your Steam Library, right-click on Borderlands 2 and select "Properties."
2) Click the "Updates" tab.
3) Uncheck "Enable Steam Cloud synchronization for Borderlands 2."
4) Click "Close."