Error Creating Flat Buffer On Line

[ScottDean]

I am getting a generic 999999 error trying to create a line buffer in 10.2.1 against a feature class that is in a projected coordinate space.  It will work when using the Round option bu@@t not when using the Flat option.    Is this a known issue?  It was working with ArcGIS 10 and I just upgraded to 10.2.1 and now same code generates the error.  It will also work (Round or Flat) if using GCS NAD27.

Coordinate System below.

Projected Coordinate System:	NAD_1927_UTM_Zone_15N
Projection:	Transverse_Mercator
False_Easting:	1640416.66666667
False_Northing:	0.00000000
Central_Meridian:	-93.00000000
Scale_Factor:	0.99960000
Latitude_Of_Origin:	0.00000000
Linear Unit:	Foot_US

Geographic Coordinate System:	GCS_North_American_1927
Datum:	D_North_American_1927
Prime Meridian:	Greenwich
Angular Unit:	Degree

[NeilAyres]

I would look at the source of the data rather than the tool which used to work before.

999999 errors are the funnies.

So paths to data, its name (all not containing spaces and other nasties).

Coord sys seem fine. Projected, which is important for distance measures.

[DanPatterson_Retired]

Same version of arcmap had a NIM (NIM098245) when negative buffers were used, but this indicates a certain level of flakeyness, it had been corrected in 10.4... so upgrade or convert it out to a shapefile and try it in a simple path location or try it in a separate gdb... ditto on the path and filename simplicity