extent is invalid for geotiff

[John Bonk]

I am very new at this.  I am having problems serving a geotiff image
with the following attributes:

Projection Method: CT_Equirectangular
    ProjCenterLatGeoKey: 0.000000 (  0d 0' 0.00"N)
    ProjCenterLongGeoKey: 0.000000 (  0d 0' 0.00"E)
    ProjFalseEastingGeoKey: 0.000000 m
    ProjFalseNorthingGeoKey: 0.000000 m

Corner Coordinates:
Upper Left    (-13053641.300,5752577.812)
Lower Left    (-13053641.300,3358256.867)
Upper Right   (-9325729.471,5752577.812)
Lower Right   (-9325729.471,3358256.867)
Center        (-11189685.386,4555417.340)

I have tried all sorts of variation of these number in the EXTENT field
but  I have
been getting an 'extent is invalid' message.

Can anyone help me express the EXTENT and PROJECTION to read this file?

John
=======================================
John Bonk
SSAI/NASA GES DISC
Phone:(301) 614-5280
Fax:  (301) 614-5268
For more information about
the NASA GES DISC and its services:
http://daac.gsfc.nasa.gov/