仅在名称以“c”开头的Excel VBA运行时错误1004

That's right. If I change the 'C' in 'Chart_Series_W_Gain_AAPL' in the following code to any other letter the code works. Otherwise it throws an Error 1004 at the Series.Formula assignment. In fact, if I use any random name that begins with 'c' the code fails but not otherwise. I've tried closing Excel and reopening, but same issue. I came across this because I had been naming my chart series defined names beginning with the name of the chart, but then I decided that was confusing and I attempted to prepend defined name used as a chart series with "Chart_Series_". Pretty benign change, one would think. That's right. If I change the 'C' in 'Chart_Ser