Member Rara Avis
The limitation, Janet, isn't in the Personal Library - you can theoretically have as many entries as you like - but rather, the limitation you've discovered is in the Archived forums.
You may remember a time when we lost access to the Archives for several months because the web server ran out of disk space? The solution to that problem was to make the Archives only available "on demand." When you click on a link in a current forum, like Open #14, the web page already exists and comes up fast. But when you click on a link in an Archive forum, the web page is built then and there, from our database, and only exists for a relatively limited time. If you bookmark the web page, or add it to your Personal Library, it will only be valid until the next maintenance sweep (typically a monthly procedure). Then the web page disappears, though the poem still exists in our database - ready to be recreated for the next "on demand" reader. With the size of our existing database, this is the only possible way to keep everything always available.