Once an asset is disposed of, it cannot be edited. However, it is possible to delete the disposal and edit the asset. 
  1. Open the Asset
  2. Select the Activity tab 
  3. Select the Disposal Transaction
  4. Click the Delete button on the gray bar above the list of transactions
  5. Enter a reversal post date for the transaction (if posted)
  6. Make any changes necessary to the asset
  7. Once all changes are made, create a new disposal transaction.