Every time I open lightroom Im noticing my lightroom settings in particular at least the export settings are reset. Im using the latest version updated, on Windows 7
my preferences file in appdata/roaming/adobe/lightroom/preferences is showing as last updated 15/9/2015
I would suggest you to first Backup your catalog so that in case Preferences are corrupt you have the settings backed up.
Also backup your Presets in Lightroom
Then move the Preferences File "Lightroom5Prefernces.agprefs located in appdata/roaming/adobe/lightroom/preferences to Desktop and restart Lightroom
Thankyou, seems to have worked