If you are seeing an error like the below, this means that the webpage you are attempting to view is expired and needs to be reset. To do this, close your browser and click the link again. This will reset the duration of the document.
For a more technical explanation, when you click the link to view the document, you are using the Website server's computing power to view the document. Each document has an expiration time to avoid overusing the server and causing it to crash. After some time, the server forcibly stops the document from taking computing power. You can restart that cycle by clicking to view the document again.