Source : Webster's Revised Unabridged Dictionary (1913)

Reconvert \Re`con*vert"\ (-v?rt"), v. t.
   To convert again. --Milton.

Reconvert \Re*con"vert\ (r?*k?n"v?rt), n.
   A person who has been reconverted. --Gladstone.

Source : WordNet®

reconvert
     v : convert back; "Hollywood is reconverting old films"