Hi Neil,
you can`t put strings and numbers in the same array. An Array accepts only one data type, in this case either numbers OR strings.
What you can do is write the strings (tab delimited, with control/return at the end) into the required file before calling the "write to spreadsheet" VI. It`s important to then wire the VI so that it Appends to the existing file, otherwise it`ll be overwritten.
Then you should have your spreadsheet file with headers.
Shane.
Using LV 6.1 and 8.2.1 on W2k (SP4) and WXP (SP2)