What is XIACMTT.TMP

A friend of mine had the the following XIACMTT.TMP item appear on the left hand side of the Netscape window. This appeared between her logging off this morning and logging on this afternoon (dial up connection). The PC is a very old Pentium Pro 200Mhz running Win 95 version A. Anybody got any ideas what XIACMTT.TMP refers to.