You can save an endless number of sites in your Site Manager. The error you received is because you did
not save the site to your Site Manager list from your Quick Connect list. The Quick Connect list will hold up to 50 sites (or logins with various L/Ps) and will bump older sites off as newer sites are Quick Connected to.
I recommend saving sites to the Site Manager via menu:"Sites > Add Current Site..." once you are connected to a site... Or by Site Manager [F4].
If you want to increase the number of sites that will be kept in your Quick Connect History, please read
this thread.
- Raccoon