File Extension CRDownload
If you use Google Chrome, there is a strong possibility that you have seen files with the extension ".crdownload" in your download directory. Google Chrome creates one each time you start downloading a file.
The .crdownload are automatically renamed when a download completes successfully, but can be left if there is an error in the download.
When (and Why) Chrome Creates These
Google Chrome creates .crdownload for your downloads. For example, let's say you start downloading a music called Song.mp3 in Google Chrome. "Song.mp3.cdownload" will appear in your downloads folder. This will grow in size while Chrome continues the download. When Chrome finishes downloading the entire file, Chrome will rename it to Song.mp3, removing the .crdownload suffix.
The .crdownload extension indicates that the file has not yet finished downloading. Other web browsers can store downloads in progress in a different folder and move them to your downloads folder when they finish, but Chrome simply stores the incomplete file in your Downloads folder.
If you see a .crdownload, check your Downloads list in Chrome. You can see in the Download tray at the bottom of your Chrome window or click on the menu and select Downloads. If it is still being downloaded, do not delete the .crdownload file - just let Chrome finish downloading it.
Of course, if you really do not want to download it anymore, you can cancel the download in Chrome. Chrome will automatically delete the associated .crdownload file when you cancel the download.
Chrome Can Summarize Download With These Files
You can have a .crdownload file out there even though Chrome is not downloading something at the moment. Open the Downloads page in Chrome and you may see that a download is incomplete. This indicates that Chrome was downloading a file, but there was a problem - your Internet connection may have been interrupted, or the server may have cut the connection. You can also "pause" a download and summarize it later, in which case Chrome will keep the .crdownload file there.
You can try to click on the Summarize button. Chrome will try to summarize where it left off and add the rest of the file to the .crdownload . But summarizing may not always work properly. You can simply want to download the file again from the beginning.
When can you delete it?
You are free to delete it at any time you like. If no download is in progress and you do not need to summarize a download using the file, go ahead and delete it.
You will want to delete the .crdownload file when you no longer need it. For example, if you see your Downloads folder and see files called Song (1) .mp3 and Song.mp3.crdownload, you can delete it ending in .crdownload. This is simply an incomplete download file that you do not need.
If you see an old for a file that you tried to download some time ago, you can definitely delete it. This can happen if you skip and do not clean the Downloads folder regularly.
If you try to download and come back to see a .crdownload file sitting in your Downloads folder, it failed to download properly (or continues to download). You can go to the Chrome download manager and retry the download. The .crdownload provides a reminder that you were going to download a specific file, but that it did not arrive successfully.
So that's what this format is - a partially complete Chorme download. It is a download in process, a failed download, or a slow download.