Sec Form 4 Filing - SNYDER CAROLE B @ FIRSTENERGY CORP - 2007-03-01

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person SNYDER CAROLE B 2. Issuer Name and Ticker or Trading Symbol FIRSTENERGY CORP [ FE] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Senior Vice President (Last) (First) (Middle) 76 SOUTH MAIN STREET 3. Date of Earliest Transaction (MM/DD/YY) 03/01/2007 (Street) AKRON, OH44308 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 03/01/2007 M 11,100 ( 1 ) A $ 29.71 26,171 D Common Stock 03/01/2007 M 9,150 ( 1 ) A $ 38.76 35,321 D Common Stock 03/01/2007 M 9,150 ( 1 ) D $ 62.006 26,171 D Common Stock 03/01/2007 M 11,100 ( 1 ) D $ 62.006 15,071 D Common Stock 1,309.822 I by Savings Plan

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Phantom 3/05D $ 1 02/25/2005 03/01/2008 Common Stock 1,618.492 1,618.492 D Phantom 3/06D $ 1 03/02/2006 03/02/2009 Common Stock 3,393.648 3,393.648 D Phantom 3/07D $ 1 ( 2 ) 03/01/2007 A 2,759.28 ( 3 ) 03/01/2007 03/01/2010 Common Stock 2,759.28 $ 62.89 6,648.18 D RSUP1 $ 1 03/01/2008 03/01/2008 Common Stock 2,802.083 2,802.083 D RSUP4 $ 1 03/01/2009 03/01/2009 Common Stock 2,262.87 2,262.87 D RSUP6 $ 1 ( 2 ) 03/01/2007 A 1,773 03/01/2010 03/01/2010 Common Stock 1,773 $ 62.25 1,773 D Stock Options (Right to buy) $ 29.71 03/01/2007 M 11,100 03/01/2004 03/01/2013 Common Stock 11,100 $ 62.006 0 D Stock Options (Right to buy) $ 38.76 03/01/2007 M 9,150 03/01/2005 03/01/2014 Common Stock 9,150 $ 62.006 9,150 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other SNYDER CAROLE B 76 SOUTH MAIN STREET AKRON, OH44308 Senior Vice President Signatures Edward J. Udovich, POA 03/05/2007 Signature of Reporting Person Date

Explanation of Responses:

( 3 )This award was based on the average of the daily closing prices of FirstEnergy during the month of February, 2007 - 2,299.40 of these shares are vested (i.e., non-forfeited) immediately; 459.88 of these shares become vested (i.e., non-forfeited) on 3/1/2010. ( 2 )1 for 1 ( 1 )This stock option was exercised in accordance with a 10b5-1 Plan signed by Carole Snyder on 12/20/2005.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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