SUMMARY ORDER

Plaintiff-appellant Ronnie Dixon Siner (“Skier”), pro se, appeals from the April 1, 2011 order of the District Court granting summary judgment to defendants-appel-lees on his claim, brought pursuant to 42 U.S.C. § 1983, that his sentence was calculated incorrectly. Judgment was entered on April 5, 2011. We assume the parties’ familiarity with the underlying facts, the procedural history of the case, and the issues on appeal.

We review an order granting summary judgment de novo, drawing all factual inferences in favor of the non-moving party. See, e.g., Paneccasio v. Unisource Worldwide, Inc., 532 F.3d 101, 107 (2d Cir. 2008). “Summary judgment is proper only when, construing the evidence in the light most favorable to the non-movant, ‘there is no genuine dispute as to any material fact and the movant is entitled to judgment as a matter of law.’ ” Doninger v. Niehoff, 642 F.3d 334, 344 (2d Cir. 2011) (quoting Fed. R.Civ.P. 56(a)).

Having conducted a de novo review of the record in light of the above standards, we now affirm for substantially the reasons set forth by the District Court in its Decision and Order of April 1, 2011. On appeal, Siner has failed to identify any errors in the magistrate judge’s decision or advance any specific reasons why that decision should not be upheld on appeal. Accordingly, he has waived any specific challenges to that decision. See LoSacco v. City of Middletown, 71 F.3d 88, 92-93 (2d Cir. 1995) (holding that issues not raised by pro se litigant in an appellate brief were abandoned, and explaining that, although “appellate courts generally do not hold pro se litigants rigidly to the formal briefing standards ... [courts] need not manufacture claims of error for an appellant proceeding pro se, especially when he has raised an issue below and elected not to pursue it on appeal”).

We have considered all of Siner’s general challenges to the magistrate judge’s decision and found each of them to be without merit.

CONCLUSION

We reject all of Siner’s claims on appeal. Accordingly, the April 1, 2011 order of the District Court is AFFIRMED.