From another board:

Use more flexible "external library" feature: open C:Users[YOUR WINDOWS LOGIN]AppDataRoamingPoser Pro11 folder; open poser.ini file in notepad, change line "LIBRARY_EXTERNAL_CLIENT 0" to "LIBRARY_EXTERNAL_CLIENT 1", save and close the file; launch Poser, in the library tab you will see something like "Release URL = http://127.0.0.1:11530/nonVirtualAssets/ContentLibrary/release-1.9.1/ContentLibrary/ContentLibrary.html"; copy the URL, open your favorite browser, paste the URL, press [ENTER]