http://bugs.winehq.org/show_bug.cgi?id=5139
------- Additional Comments From jasonspiro3+wine@gmail.com 2006-19-05 13:44 ------- Tom, the only cab files on my Dell OEM WinXP CD are: \i386\mmssetup.cab modem.cab osc.cab sp1.cab win.cab winsys.cab winsys32.cab \i386\win9xmig\mapi...\80.cab 801.cab 802.cab 803.cab 98map.cab 98omi.cab 40.cab 40a.cab 40sp3.cab 40sp4.cab 50sp1.cab 50sp2.cab \support\tools\deploy.cab support.cab sup_pro.cab sup_srv.cab
There are a bunch of ca_ files too but none of them are named accessor.ca_. Also, a Google search for accessor.cab finds only Wine-related issues.
I think that ignoring the return value isn't dangerous, though perhaps we should print a trace or msi:err message when the return value of extract_cabinet_file is or isn't "success".