Hacking Removing the Profile ID from an Animal Crossing: City Folk save for use w/ wiimmfi

[mooglazer]

I'd like to play Animal Crossing: City Folk on wiimmfi, but would prefer to use my existing save file (rvforest.dat). I'm familiar with hex editing and need to remove the existing Profile ID/Friend Code from my save file (wiimmfi needs to generate a new one, so I'm trying to blank out the old one).

From some research, I've read that the PID is stored in offset 40-43 (assuming this is correct?), and that the checksum needs to be updated:

The data you are trying to edit has a checksum at offset 0x20. The checksum is calculated over 0x111C bytes of data, starting at offset 0x24 and ending at 0x1140.

I modify the data at offsets 40-43 to '00 00 00 00' and then update the checksum at 0x20. However, AC:CF still complains that the save is invalid.

Am I doing something fundamentally wrong or am I missing any information?

I put together a really simple gallery showing what data I'm modifying/selecting, in case it matters: https://imgur.com/a/iSpo3

Thanks for your help!

 

[DaMan4169]

I've never played AC:CF, had to modify a game save like this, or connected to Wiimfi but...

Assuming your instructions were correct, you may be ending at the wrong point, you calculated thru 0x113F.

starting at offset 0x24 and ending at 0x1140.

You should take your unmodified Original Save and run a CRC32 checksum to see if it calculates to EEABBEDC so you know where to end. 0x1140 is just a bit outside of the area you had calculated. Of course your instructions could have been written to mean just before 0x1140 not including it. Once you can match the original CRC, you'll know you have that part of it correct then make your edit.

I have to ask the other question as well. Are you starting from the correct location. If the CRC is in 0x20 - 0x23, are you excluding that and just calculating the data after it? You had to scroll down in your pic so it doesn't show the start point.

 

[mooglazer]

I've never played AC:CF, had to modify a game save like this, or connected to Wiimfi but...

Assuming your instructions were correct, you may be ending at the wrong point, you calculated thru 0x113F.


You should take your unmodified Original Save and run a CRC32 checksum to see if it calculates to EEABBEDC so you know where to end. 0x1140 is just a bit outside of the area you had calculated. Of course your instructions could have been written to mean just before 0x1140 not including it. Once you can match the original CRC, you'll know you have that part of it correct then make your edit.

I have to ask the other question as well. Are you starting from the correct location. If the CRC is in 0x20 - 0x23, are you excluding that and just calculating the data after it? You had to scroll down in your pic so it doesn't show the start point.

I've got the offsets correct, and the length area being checksummed is correct. I believe there may be another checksum I need to update, but I'm not familiar with the save file format.

Any help from others (who have actually worked with AC:CF save files) is appreciated.

 

[DanielKimJS]

The entire field between 0x00 and 0x1140 contains the information of the PID(Friend codes) and your friends list. Not only 0x40 to 43. You can see the PID data on 0x60 to 63.

--------------------- MERGED ---------------------------

you should replace entire the hex code between 0x00 to 0x1140