Why do I see "Unexpected server error" when trying to view a PDF?  

You might see "Unexpected server error" when trying to view a PDF because your firewall is blocking the domain that is sent back from our system when retrieving content.

To ensure that your firewall is not blocking the retrieval of the content, please request that your IT team whitelists the following URLs on your firewall and network:

• https://s3-eu-west-1.amazonaws.com/fusion-universal-videos-production/
• https://s3-eu-west-1.amazonaws.com/fuse-public-assets/Public+assets/
• https://s3-eu-west-1.amazonaws.com/fusion-universal-assets-production/
• .fusion-universal.com
• .fuseuniversal.com 
• https://cdnjs.cloudflare.com/
• https://fuse-public-assets.s3-eu-west-1.amazonaws.com/
• https://lxd.fuseuniversal.com/ (CDN variant)
• https://s3-eu-west-1.amazonaws.com/fuse-public-assets/ (Old S3 url)
• https://code.jquery.com/

If this error occurs while using Internet Explorer, do the following:

1. Open Internet Explorer.

2. In the top-right corner of the screen, click Settings. 

3. Click Internet Options. 

4. Click the Security tab.

5. Click Custom level. 

6. Click Miscellaneous.

7. Click Access data sources across domains.

8. Select Enable.