2.8 Error conditions

Errors will mainly be displayed in pop-up windows similar to the one in Figure 1.

When a user tries to load an HTML file that has broken tags or is incorrectly formatted, they will get the following error: "HTML file incorrectly formatted."
When a slide is displayed with external content, such as an image, and that content cannot be found, an error image will be displayed.
When a user tries to add an absent student to a chat, they will get the following error: "Unable to add absent student to chat."
When a user tries to save and there isn't enough disk space remaining, they will get the following error: "Not enough free space remaining."
When a user tries to send a message in chat and the message fails to send, they well get the following error: "Message failed to send."
When a user tries to load a file and the file being loaded doesn't exist, they will get the following error: "File not found."
When a user tries to save a file with the same name as a file that already exists, they will be prompted whether or not they want to overwrite the file.
When a user attempts to log in with the wrong username or password, they will get the following error: "Incorrect username or password" and be prompted to log in again.
When a user attempts to log in with the wrong username or password 5 times, it will take 10 seconds before they are prompted to log in again.

Figure 1: Error window