When you design a form template, Microsoft Office InfoPath automatically selects the appropriate security level for the functionality required when users fill out forms based on your form template. This setting enables the minimal level of trust that is needed for the form. For example, the Restricted security level limits the ability of a form to access data on other domains, and files and settings on a user's computer. You can override the default setting and manually choose a different security level when you design a form template. Find more information about the security levels of InfoPath form templates in the See Also section.
All new, blank form templates, except those with managed code, use the Restricted security level by default. As you add certain features to your form template, the security level is automatically raised to Domain level.
Note: To add or edit managed code, you must have Microsoft Visual Studio Tools for Applications (VSTA) installed on your computer. Microsoft .NET Framework 2.0 and Microsoft Core XML Services 6.0 must be installed before you install VSTA. To install VSTA, in Control Panel, open Add or Remove Programs, locate 2007 Microsoft Office system, and then click Change.
It is a good practice to use the appropriate security level for your form template to help your users avoid unnecessary security risks.
To set the security level for a form template, do the following:
On the Tools menu, click Form Options.
Under Category, click Security and Trust.
Under Security Level, clear the Automatically determine security level (recommended) check box.
Click the security level that you want.
Note: If the form template requires a Full Trust security level, the form template must be either installed on the user's computer or digitally signed with a trusted root certificate. Otherwise, the user will not be able to grant full trust to a form based on that form template, and some of the features in the forms that they fill out may not work. Installation files for form templates can be made by using the InfoPath Publishing Wizard.