Do you have a Bing Map Key and have you attached in Raster Manager ? https://communities.bentley.com/products/3d_imaging_and_point_cloud_software/w/wiki/25042/working-with-bing-maps
or perhaps you have used CONNECT Edition in the past were new functionality was added https://communities.bentley.com/products/microstation/b/microstation_blog/posts/new-in-microstation-connect-edition-update-7-bing-map-background-map
The background map option is a feature only available in the CONNECT Edition of MicroStation that was added in Update 7.
https://communities.bentley.com/products/microstation/w/microstation__wiki/37199/how-to-use-background-of-bing-map-in-microstation-update-7
The only integration in V8i is through the raster manager.
Answer Verified By: Jayson Perry