Sessions will typically time out after two hours without a server request. Typing in a text box does not interact with the server, so the system will think you are idle, even if you have been typing a long answer. You will need to click on a link or a button for your session to stay active. Most quizzes and tests have a "save" option and we highly recommend you save your work frequently.
Alternatively (or in conjunction) you can keep a second browser open to your course and randomly navigate around in the course every so often to make sure the system doesn't time you out.
For forum posts that might require a long time to compose, we recommend that you type out your post in an external program (like Notepad or Microsoft Word) and copy from the document and paste into the composition box when you are ready to post. Please note, if you type into Microsoft Word, you will likely need to paste your work into a plain text program first (such as Notepad) to get rid of all of the extra text that Microsoft Word uses. The system does not recognize this coding and your post may not look right.