Firewall, you may wish to try disabling it temporarily to see if this fixes the issue. If it does you may want to disable it for deviantART.
Anti-virus, you may wish to try disabling it temporarily to see if this fixes the issue. Some Anti-Virus programs have certain features that may cause conflicts such as Ad-blockers. If disabling it works you may want to disable the particular feature or find a way to put deviantART on the safe list also called white listing.
Your provider may be having issues connecting to some of our servers.
It's possible your school has blocked some of our servers.
If none of these suggestions Help, please contact the Help Desk.