File size limit on miniSD card?

Hi,

Just wondering if anyone knows of any limitations or restrictions on reading a file written on a miniSD card.
The reason I ask is because I have a made my Arduino Uno into a datalogger that saves data to the miniSD ever 30 seconds. When I have it set up to e-mail every 5 minutes or every 10 minutes it works fine; however, when I change my e-mail period to something longer like 1 hour or 1 day, the e-mails no longer work.

Could this be because the file is too large?

The FAT16 file system can handle files up to 2GB. i suspect your email server is the one with the size limitation.