Error in SWAT Weather Data Input – “Index was outside the bounds of the array (line 0)”

[subham roy]

Hello everyone,
I am working with the SWAT model using QSWAT and facing an issue while loading weather data. When I input my weather files (Tmax, Tmin, etc.), I get the following error:
“Index was outside the bounds of the array: in reading line 0.”
I have checked the file, but I am not sure what is causing this issue. My data is in .txt format and follows the standard SWAT structure (as shown in tutorials), but the error still appears.
Could someone please help me understand:
What exactly causes this error?
Is it related to file formatting, headers, or missing values?
How can I fix it?
Any guidance would be really helpful.
Thank you!