Add all of these to your exemption lists on webfilters, firewalls and caching servers.

https://homework.realsmart.co.uk

https://portfolio.realsmart.co.uk

http://smartfuse.s3.amazonaws.com/

https://smartfuse.s3.amazonaws.com/

https://rlsmart.net

http://rlsmart.net

www.rlsmart.net

https://smartadmin.realsmart.co.uk

http://smartadmin.realsmart.co.uk

http://stuff.realsmart.co.uk

http://docs.google.com

https://docs.google.com

http://classroom.google.com

https://classroom.google.com

https://sites.google.com

http://sites.google.com

http://mail.google.com

https://mail.google.com

mail-attachment.googleusercontent.com

http://drive.google.com/

https://calendar.google.com

files.rlsmart.net.s3.amazonaws.com

dev-smart-site-assets.s3.amazonaws.com

Advanced list - ie if you’re still having problems - thanks to Chromestead

Google Drive for your PC/Mac

• www.google.com:443/HTTPS

• accounts.google.com:443/HTTPS

• clients3.google.com:443/HTTPS

• talk.google.com:5222/XMPP

• drive.google.com:443/HTTPS

• www.googleapis.com:443/HTTPS

• ssl.gstatic.com:443/HTTPS

• *.docs.google.com:443/HTTPS

• *.drive.google.com:443/HTTPS

• *.googleusercontent.com:443/HTTPS

Google Drive on the web

• s.ytimg.com:443/HTTPS

• video.google.com:443/HTTPS

• lh3.google.com:443/HTTPS

• lh4.google.com:443/HTTPS

• lh5.google.com:443/HTTPS

• lh6.google.com:443/HTTPS

• mail.google.com

For Drive, Docs, Slides, and Drawings

• http (port 80) connection to docs.google.com, docs[N].google.com and*.docs.google.com, where is a number from 1 to 9 eg docs3.google.com

• https (port 443) connection to docs.google.com and docs[N].google.com.

• https (port 443) connection to *.docs.google.com.

Sheets

• http (port 80) connection to spreadsheet.google.com, spreadsheets.google.com,spreadsheets[N].google.com, and *.spreadsheets.google.com.

• https (port 443) connection to spreadsheet.google.com,spreadsheets.google.com and spreadsheets[N].google.com.

Sites

• http (port 80) connection to sites.google.com.

• https (port 443) connection to sites.google.com.

• https (port 443) connection to *.sites.google.com.

• https (port 443) connection to *.googlegroups.com.

Drive, Docs, Sheets, and Slides

• https (port 443) connection to ssl.gstatic.com.

• https (port 443) connection to www.google.com.

• https (port 443) connection to *.googleusercontent.com.

• https (port 443) connection to gg.google.com.

• https (port 443) connection to *.googleapis.com.