You can find this section in HostBill Admin → Settings → Products & Services → Your order page → Your product → Components → Forms → Add new form field → Custom/Extra field types → File upload.

Basic settings
In the Basic settings section you can configure:
Field name - the name for this field
Required field - choose if you want the field to be required to proceed
Description - optionally you can add the description for the field
Form group
Advanced settings
In the Advanced settings section you can configure:
CSS Class - field container will be displayed with this css class
Group - supported by some order pages to group option
Variable name - to use in emails
Admin only - if this option is enabled only admin can see this field
Show in cart - display this field during order
Show in Invoice - choose when to add field description to invoice line:
Default - show when priced or enabled in cart and not empty
Priced - show when selected value isn't free
Force - show even when it's empty or free
File upload settings
In the File upload settings section you can configure:
File count limit - maximum number of files customer can upload through this form
Allowed extentions - comma separated list of allowed extensions (i.e.: .png,.pdf,.jpg)
Max file size limit - max uploaded file size (in MBytes)
Min file size limit - min uploaded file size (in MBytes)
Client area sample view
Video overview

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