[Kevin82485]

Don't know if you ever figured this out, but it is because of the below reason. I've copied and pasted this from another thread that I posted it in (with some minor edits).

This error is because a player for some reason does not have a date of birth entered. You can quickly tell which player it is by browsing to a team that throws the error, then select Tools > Export as > as Excel. Open the spreadsheet and look for a player with an empty DOB field.

Unfortunately if you try to edit the player with the issue, you receive the error again and cannot edit him.

There are two ways to fix this...I prefer the 2nd method I have below

One way that I have found to fix this is to right click on any other player on the roster, select "Copy Player", then right click on the player with no DOB and select "Paste Player". You will have to re-edit/re-create the player you are copying over, but you will at least be able to edit that player again and stop the error from appearing.

Another way to fix it is in game, edit these players and you will see that they have a Skin Tone of "January". Change this to something else and save the roster. Then open the roster in the editor and browse to the player with the issue. You will now be able to edit them, however their Skin Tone will be blank and their DOB will be 12/30/1899 making them over 100 years old. Should be able to correct these two fields and all will be right.