I have the E! files here at http://www.synthzone.com/midi/yamaha/dx7II/E!/
There is a read me with them that explains how to load them so I'll include it below. Maybe that will help, plus you can always try creating a new disk as a backup.

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The files accompanying this file are the 28 original files from the Grey Matter Response, Inc. E! Demo disk included with the E! expansion chip for the Yamaha DX7IIFD synthesizer. The E! modification expands the internal memory storage capacity to 256 single voices and 128 performances including special 8-way Splits, Floating Splits, Chord and Player modes. E! also adds 8-voice multitimbrality and 16 track sequencing capabilities to the instrument.

The six E-Demo.E?? files comprise the E-Demo ERAM. The new ERAM data storage type contains data for 4 banks x 64 voices, 4 banks x 32 performances, sequencer data up to 22,000 events, Player and Chord songs, 12 tone microtunings, and all engine data. The E-Demo.C01 file contains fractional scaling data for the seven voices that use fractional scaling. The remaining x.S?? files containing the seven songs associated with sequencer performances 1-7.

To use these files with a DX7IIFD equipped with E!, copy them to a 720k DOS-formatted 3-1/2" diskette and follow these instructions:

Note: All voices, performances and sequences in internal memory will be overwritten. Save all unsaved voices, performances and sequences to a disk or cartridge before proceeding.

1. Turn internal and cartridge Memory Protect off under the Utility Tune [button #14] menu.
2. Start SE!quencer under the Utility Tune [button #14] menu.
3. Choose 4 = Util followed by 4=Global
4. Select 1=Erase SEQS and press the [YES] button when asked DESTROY ALL SEQUENCES? [yn]
5. Press [NO] to exit the sequencer, [YES] to confirm.
6. Insert the diskette containing the E! demo files into the synthesizer's diskette drive.
7. Find the Disk ERAM menu under the UTILITY DISK [button #16] menu.
8. Press [YES] to view the Disk ERAM directory.
9. Use the no/yes buttons to display File 1 E-Demo.
10. Use the cursor buttons to move to the Load option and press [YES]. At the prompt press [YES] again. The loading process takes about a minute and a half.
11. When the data is fully loaded, the display responds with "Complete".
12. Insert a RAM4 cartridge and format for fractional scaling data.
13. Find the Disk CRT menu under the UTILITY DISK [button #16] menu.
14. Press [YES] to view the Disk CRT directory.
15. Use the no/yes buttons to display File 1 E-Demo.
16. Use the cursor buttons to move to the Load option and press [YES]. At the prompt press [YES] again.

You can now enter Single mode and listen to the 256 voices from the E! demo disk.

After pressing the [PERFORMANCE] button, you can select one of the 32 demo performances in bank 1. The first seven performances are sequence performances. If you choose one of these, the corresponding sequence will be loaded from the diskette. When the song is fully loaded, press the [1-32 33-64] engine button to start/stop playback.

The remaining performance memories in bank 1 contain examples of the other new performance modes.

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