Have any readers who use statistical functions in Microsoft Excel ran into the annoying random abscence of the 'data analysis' option from the tools menu? (To access it in the first place you have to click on 'add-ins' from the tools menu, and with access to the Excel installation CD choose to install the 'Analysis Toolpak - VBA').
I continually go to run a regression only to find that much of the time that the data analysis option has gone AWOL. To get it back, I've to reinstall the analysis toolpak in additon to occasionally needing to exit and reboot Excel. Thus far I've always been able to make it recidivistic instead of having it disappear permanently, but I fear it's only a matter of time. Curious, and quite irritating.