Narrative:

I approved a pointout from an adjacent sector on a C172 for a GPS 20 approach to fit at 4000 ft then a PA32 departed mht VFR to oxc. The PA32 requested an IFR clearance to get above WX. I issued a climb to 4000 ft in conflict with the C172. The other controller advised me of the impending situation. I then descended the PA32 to 3000 ft and issued a traffic alert.

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Original NASA ASRS Text

Title: A90 CTLR EXPERIENCED OPERROR AT 3200 FT WHEN VFR ACFT WAS ISSUED IFR CLB AND CONFLICTED WITH C172 ON GPS APCH TO FIT.

Narrative: I APPROVED A POINTOUT FROM AN ADJACENT SECTOR ON A C172 FOR A GPS 20 APCH TO FIT AT 4000 FT THEN A PA32 DEPARTED MHT VFR TO OXC. THE PA32 REQUESTED AN IFR CLRNC TO GET ABOVE WX. I ISSUED A CLB TO 4000 FT IN CONFLICT WITH THE C172. THE OTHER CTLR ADVISED ME OF THE IMPENDING SITUATION. I THEN DSNDED THE PA32 TO 3000 FT AND ISSUED A TFC ALERT.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.