File Upload Attribute - File Size Limit?

I have ZC v.1.3.8 installed for a client who will be selling customized photo announcement cards. I've set up a bunch of product attributes that will allow customers to enter the custom info for their cards when they add the product to their cart. I'm also using a product attribute file upload so that customers can upload the image(s) they want to go on their custom cards. The uploaded files are print-quality photos, so they are large files (2-4MB). If the card requires just one photos, the file upload works fine. If multiple file uploads are required, however, Zen Cart kicks back an error message that says "Warning File was too large to upload!" Is there somewhere I can change the file upload limit allowed? Or another way I can make this work (maybe some way to upload each file one at a time, rather than all at once)?

There are 2 parts to setting file upload size limits:

a) Admin->Configuration->Maximum Values->Maximum Upload Size

b) Your server's PHP configuration. You can check the allowed limits by going to Admin->Tools->Server Info and looking at these:
PHP File Uploads: On
Max Size: xxM (this is the PHP upload_max_filesize setting)
POST Max Size: xxM (this is the PHP post_max_size setting)

Both the "Max Size" and "POST Max Size" need to accommodate the file sizes you intend to use, and should be at least as big as the amount you set in (a) above.

You may have to work with your hosting company to set those values appropriately.

Thank you so much! That was exactly what I needed. I upped the ZC file upload limit, and everything seems to be working as needed now. :)