Excel 2007: Lines not displaying on Scatter Plots
 

I have equipment that spits out system variables every minute for
weeks/months at a time. There are numerous gaps in the data when the system
is not "sampling", from minutes to days at a time, though I maintain
continuity of the Date/Time stamp that I use as the x-axis. So the data sets
I use are enormous, maximizing the capabilities of Excel (i.e. 30,000 points
per data series and typically no more than 6 data series per plot). The
chart data references multiple worksheets, so a Scatter Plot is the only
appropriate option.

I have recently installed Office 2007, though some programs of Office 2003
are still loaded on the system. When trying to plot Lines (w/ no Markers) on
Scatter Plots, the lines will display appropriately in the Legend but not in
the Chart Area. The only way I can get data to display in the Chart Area is
by selecting Markers (w/ no Lines). This is not an appropriate work-around,
and I have NEVER had an issue creating plots like this in Excel 2003.

Any assistance would be greatly appreciated.