Levi Wooderts, Jr., federal prisoner # 29639-077, seeks leave to proceed in for-ma pauperis (IFP) to appeal the dismissal of his 28 U.S.C. § 2241 petition challenging the 20-year sentence and $386,589.03 restitution order he received, after a jury trial, for conspiracy to alter or remove motor vehicle identification. The district court denied IFP, certifying that the appeal was not taken in good faith. By moving for leave to proceed IFP, Wooderts is challenging the district court’s certification. See Baugh v. Taylor, 117 F.3d 197, 202 (5th Cir. 1997); Fed. R.App. P. 24(a)(5). However, Wooderts has not demonstrated any nonfrivolous ground for appeal.

Wooderts argues that (1) his sentence is unconstitutional in light of United States v. Booker, 543 U.S. 220, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005), Blakely v. Washington, 542 U.S. 296, 124 S.Ct. 2531, 159 L.Ed.2d 403 (2004), and Apprendi v. New Jersey, 530 U.S. 466, 120 S.Ct. 2348, 147 L.Ed.2d 435 (2000); and (2) that a 21 U.S.C. § 2255 motion is inadequate and ineffective to test the legality of his detention.

Section 2255 provides the primary means of collaterally attacking a federal sentence based on errors that occurred at or prior to sentencing. Jeffers v. Chandler, 253 F.3d 827, 830 (5th Cir. 2001). Because Wooderts’s petition challenges errors that occurred at sentencing, it should not have been brought as a 28 U.S.C. § 2241 petition. See Padilla v. United States, 416 F.3d 424, 426-27 (5th Cir. 2005). Wooderts’s argument that he is entitled to proceed under 28 U.S.C. § 2241 based on the savings clause of 28 U.S.C. § 2255 because relief under that section is “inadequate or ineffective” is unavailing. See id. at 427.

Wooderts’s appeal does not involve legal points arguable on their merits, and it is therefore frivolous. See Howard v. King, 707 F.2d 215, 220 (5th Cir. 1983). Accordingly, the IFP motion is DENIED, and the appeal is DISMISSED as frivolous. See Baugh, 117 F.3d at 202; 5th Cir. R. 42.2