When applying new limits for a Hosted Exchange mailbox, the following error is displayed in POA Customer Control Panel (see the screenshot below):
Invalid input Incorrect or empty field value(s). Please retype info in the highlighted fields.
Typically this means that limits you attempt to modify contradict some other limit(s). Allowed value range is displayed below the incorrectly set limit.
In the screenshot above, the problem is that the 'Issue Warning' limit is set higher than 'Prohibit Send' limit, which should not be the case.
A similar message will be displayed if you configure one of the limits to be greater than the size of the mailbox.
In general, the 'Issue Warning' limit must not exceed the 'Prohibit send at' and 'Size limit' limits, and the 'Prohibit send at' limit must not exceed the 'Size limit'.
You may also get same error if there is no free resource which could be allotted. Note that even when the resource is not physically used, it can not be allotted if it has already been allotted to any service/object. Say for example, you can check the details of mailbox size allocation from CCP > Exchange > Storage Usage Report. This applies to the disk size limit. Please check the documentation regarding this calculation.
Configure the limit highlighted in red to be within the specified bounds.