Yes, you can. Anyone can try Sharimg during 15 days absolutely free. This trial will be restricted to the following: 5Gb of non-reusable space, up to 15Gb of downloads or playbacks, 20 minutes of footage uploads via web application and 2 Administrators and 3 Standard Users.
Videos allocated in Sharimg will be removed 15 days later the trial period has finished. In case of purchasing a plan within those 15 days, those videos will be maintained.
Please check your internet connection and also that the file is in the following format: .mp4 (h.264).
In case that after following the previous steps you continue having issues uploading a video is possible that you have no space left in your account. In this case you will need to delete some old videos in order to free space in your account for the video you want to upload.