There is an odd bug which I found when I selected all the fields on an opportunity record in an advanced find and then tried to export the records to excel.
What made this error annoying was the download log file was greyed out, so it was difficult to investigate.
The reason for the error is because there are two fields with the same Display name, in this case it was two fields with the name Proposed Solution.
To resolve the error you need to rename one of the fields and you will be able to export from Excel again.
You could also not select the duplicate fields and this will work around the error.
Hosk's Dynamic Blog 
FYI: This error occurs on every entity if you have two fields with the same Display name.
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Thanks. It worked 🙂
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Helpful post. Thank you
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Hosk, thanks a lot it worked, It saved me a lot of time in a time critical situation . I always appreciate the good work that you do. Keep it up fellow CRMer.
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Today we have the same problem in our project.
We have tried this solution, but unfortunately, it has not worked. Neither a problem with the number of records to export.
Finally, we have discovered the problem, a value in a picklist has been deleted!! When you re-create the value in the picklist (with the same id, of course) the problem has been solved magically. I hope you help them
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You are a gem man…. Thanks for helping us all in critical situations.
Regards,
Anuj Govil
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