First, figure out how wrong it is
A wrong edition can mean several things: an older edition, a different format, an international edition, an instructor edition, or a copy without the required access materials.
Start by comparing the book you bought against the required ISBN, edition, author, publisher, year, format, and access-code details from your syllabus or bookstore page.
Wrong edition triage
| Situation | Likely next step |
|---|---|
| Older edition | Ask whether readings and homework still line up before deciding. |
| Different format | Check whether loose-leaf, ebook, hardcover, or paperback is accepted. |
| International edition | Verify pagination, problems, access, and instructor approval. |
| Instructor edition | Ask before using it and review seller return rules. |
| Missing access code | Compare standalone access, return, and bundle options. |
Ask your instructor a specific question
Send the instructor the edition number, ISBN, format, and any access-code details for the book you bought. Ask whether that exact version will work for readings, assignments, and exams.
If the answer is no, ask whether you need the physical book, online access, or both. That prevents buying the wrong replacement.
Decide whether to return, exchange, or keep it
Return or exchange the book if the instructor says it will not work, if required access is missing, or if assignments use exact current-edition problems.
Keeping it may be reasonable if the instructor approves it, the seller return cost is high, or you can use it as a low-cost supplement while using digital access for graded work.
How to avoid the same problem next time
Use the exact ISBN from your syllabus or bookstore listing before comparing price. If you have several books to check, use /tools/multi-isbn-search; if you need to convert an older number, use /tools/isbn-converter.
Read the guides on avoiding the wrong textbook edition, older editions, international editions, and instructor editions before choosing a risky low-price listing.