SYLK File Format Error in Excel
1) Create a simple file that looks exactly like this:
ID, name, Address
123,Sally, 123 Fake Street
Make sure the CASE is accurate
2) Save the file as test.csv (or any csv file), so that it will open as a csv file in Excel.
3) Try and open it in Excel. If you followed the instructions correctly, it will not open. Instead you will get an error something like:
"SYLK: File format is not valid"
4) Now, open the file in Notepad. Change ID to id, or change it to DI if you prefer.
5) Save, and try and open again in Excel.
Why does this happen?
According to Microsoft, "This problem occurs when you open a text file or CSV file and the first two characters of the file are the uppercase letters "I" and "D"
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