x2settings.ini Gets Lost

[plugger]

Windows 7 64-bit
Xplorer2 5.5.0.0 ULT

Using the x2settings.ini file, not the registry.

Occasionally, Xplorer2 replaces my x2settings.ini with what appears to be a default version.
E.g., the pane layout changes and bookmarks vanish.
Scenario:
xplorer2 is chugging along with my settings, but if I exit and then start, it reverts.
I notice nothing peculiar about what I am doing when I exit - no running DOS command or some other background process.

Has anyone else seen this?

[nikos]

where do you keep the INI file?
in general registry is recommended unless you run xplorer2 on a USB stick (portable mode)