There could be a couple of reasons why there is trouble accessing projects or logging into ArcGIS Online.
Request an Account
If you have not previously accessed the site, you may need an account activated - request an ArcGIS Account in order to access the site.
Browsers
Most Internet browsers (Safari, Chrome, Firefox, Edge) are compatible with ArcGIS Online - it is recommended to use Google Chrome. Make sure to clear the internet cache and try these steps for logging into ArcGIS Online. If this does not resolve the access issue, contact the IT Helpdesk.
Logging In
When logging into St. Olaf ArcGIS Online, make sure that the URL contains: https://stolaf.maps.arcgis.com/
This is important because in order to access some of the collaboration tools, your account must be registered to the St. Olaf organization. If the URL does not contain stolaf in the title (ex: https://www.arcgis.com/), most likely you are on a public account.
To fix this, make sure to log out of the account, and go to https://stolaf.maps.arcgis.com/. Click on Sign in.
The log in window will appear. Do not click the Google button.
Click on the St. Olaf College button to sign into the site.
If there is a text box instead of a button, type "stolaf" in the field and click Ok. See this article for additional information on logging into ArcGIS Online (or ArcGIS Pro).