The Merit Systems Protection Board (Board) dismissed Fred F. Vaughn’s petition for review as untimely. Mr. Vaughn had requested waiver of interest accumulated on his noncontributory Federal services from 1981 to 1987. Fred F. Vaughn v. Merit Sys. Protection Bd., SF-0841-05-0426-1-1 (M.S.P.B., June 20, 2005) (Initial Decision); Fred F. Vaughn v. Office of Personnel Management, SF-0841-05-0426-1-1, 102 M.S.P.R. 1 (M.S.P.B., Apr. 21, 2006) (Final Decision). Because the Office of Personnel Management (OPM) sent a letter dated September 12, 2006 to Mr. Vaughn notifying him that they improperly calculated the amount of interest and contribution, as well as incorrectly calculated the amount under the wrong retirement system, this court dismisses Mr. Vaughn’s appeal as moot.

On February 1, 2005, the Office of Personnel Management (OPM) told Mr. Vaughn that he owed $1,359 in required contributions and $4,659 in interest on the unpaid required contributions under the Federal Employee Retirement System (FERS). OPM provided Mr. Vaughn with claim number U52 2 304 089, and under that claim number he sought a waiver of interest accumulated on his 1981-1987 Federal service. OPM denied his request. On OPM’s claim number U52 2 304 089, the Board affirmed. Initial Decision, slip op. at 5. Now, however, the amount of interest that the OPM states Mr. Vaughn owes under FERS has changed. On September 12, 2006, the OPM notified Mr. Vaughn that it had incorrectly calculated his original FERS contributions. Instead, OPM should have computed the amount under the Civil Service Retirement System. The September 12, 2006 letter gives Vaughn a new claim number: CSD 7 090 360. This new claim covers a period beginning in 1981 and ending in 1988.

After receipt of the September 12, 2006 letter, Mr. Vaughn filed a copy with this court and requested a refund of his $450 filing fee. Under the Practice Notes of Federal Circuit Rule of Appellate Procedure 52, docketing fees cannot be refunded. Upon deposit into the United States Treasury, a docket fee cannot be accessed. Therefore, though this court dismisses Mr. Vaughn’s appeal as moot, and cannot re *981 fund his docketing fee in the amount of $450, it orders the Clerk of the Court to waive a docketing fee for Mr. Vaughn’s appeal, if any, on claim number CSD 7 090 360. To receive that fee waiver in an appeal to this court involving claim number CSD 7 090 360 Mr. Vaughn should attach a copy of this order with any waiver request.