Being a well-known writer and longtime resident of Cambridge, Katherine A. Powers can be excused for expecting to find her latest book on the shelves of the local library. After all, the book about her father, the late writer J.F. Powers, has been widely reviewed, with words of praise appearing in The New Yorker, The Wall Street Journal, the Los Angeles Times, and The Boston Globe. (Powers wrote a column for the Globe for 20 years.) But after a recent visit to the Cambridge Public Library revealed that the book, “Suitable Accommodations: An Autobiographical Story of Family Life: The Letters of J.F. Powers, 1942-1963,” is not, in fact, part of the library’s collection, Powers offered to donate a copy. The library’s answer? Thanks, but no thanks. Citing a policy intended to discourage the public from dumping their unwanted volumes on the library’s doorstep, three employees of the library declined Powers’s offer. (They did inquire if the book is on The New York Times Bestseller List, and told that it isn’t, were resolved not to accept it.) Powers then did what any savvy, social media-minded person would do: She wrote about the experience on Facebook. “According to itself, the CPL is ‘a dynamic, community-oriented system providing excellent services, collections and programs to all members of the community . . . dedicated to affording the people of Cambridge resources for recreational reading.’ (Or, put another way: ‘Blah, blah, blah.’),” she wrote. Predictably, it wasn’t long before the library contacted the author and apologized. A library official we spoke to said it was an “error” not to accept the book, and the library’s policy will be tweaked to make allowances for books by local authors. The official also said that while Powers’s book is not in the CPL’s collection, there are four copies in the Minuteman Library Network, a consortium of 43 libraries. Powers, meanwhile, is moving on. “My vanity was bruised beyond redemption,” she told us. “OK, not completely without redemption.” And what did Powers do with the copy of the book she wanted to donate? She gave it to the Malden Public Library.