If you see an error message concerning file size, bit rate or resolution, please refer to the section "Files you can upload" and check the video files we support.

If uploading seems to fail (screen will turn white or browser's error screen will appear) for reasons unrelated to the video file format, this could be due to the following reasons.

- Access or uploading to niconico.com is restricted by your provider or your provider's line is  failing.

- Failure in the house-line. 

- Wireless network with bad connection. 

- Interference from security applications.

- A bug inside niconico.com.

Please try out the following methods below. If you succeed in uploading by changing the communication method, contact your internet service provider.

- Upload a smaller video file (Few KB)

- Try uploading from a net café or another web environment.

- If you are using a wireless network, try connecting with a LAN cable and upload

- If you are using a wireless network, try moving your computer close to the wireless LAN router.

- If you are using a wireless network, try moving the computer or router away from household electric appliance such as Televisions