While the specific string "questbook31expnet2112jar" has no meaningful history, the word has a rich etymological background:
: Encouraging the download of "jar" (Java archive) files that may contain malware. Historical Context of "Link" questbook31expnet2112jar link
If you have already downloaded it (but not opened it), upload it to VirusTotal to see if it triggers any antivirus detections from major vendors like ESET or Bitdefender . questbook31expnet2112jar link