If I see 'Access denied.' when opening a custom tool, should I check the file or the folder for restrictions?

Check the enclosing File Cabinet folder, not the individual file: File Cabinet restrictions apply to folders, not files. To change a folder’s restricted-access setting, log in with a role that has access, go to Documents > Files > File Cabinet, click Edit for the folder, and select restrictions for class, department, location, or group.

Which SuiteScript modules will prevent a custom tool from loading and how is the error resolved?

Custom tool scripts cannot load N/http, N/https, or N/sftp. When one or more of these modules are used, NetSuite displays a module-loading error and instructs you to remove the unsupported modules from the script.

If I restrict a parent folder after a subfolder already exists, does the subfolder automatically inherit the new restriction?

No — if a parent folder’s restriction changes after a subfolder already exists, the subfolder does not inherit the new restriction automatically. You must apply the restriction to the subfolder manually when needed.

What’s the difference between 'There was an unexpected error while executing the tool' and 'Tool execution failed'?

'There was an unexpected error while executing the tool' means the tool reached execution but failed on a line or threw an exception, and the message includes error details. 'Tool execution failed' indicates the tool did not return a result properly, a separate condition from runtime exceptions.

NetSuite Custom Tool Error Messages...

Custom tool errors identify whether NetSuite could access a tool, load its modules, create an execution context, authorize the current session, execute the script, or receive a result. Start with the exact message. For access errors, review the tool’s File Cabinet folder restrictions; for module errors, remove the listed unsupported modules.

What do custom tool error messages mean?

The following messages can appear when custom tools are accessed or run. Their descriptions distinguish access, module-loading, parameter, preparation, session-permission, execution, and result-return problems.

Error message	What NetSuite indicates
`Access denied.`	The user’s role does not have access to the File Cabinet folder where the tools are located.
`Couldn't load modules in the custom tool script because it uses unsupported modules. Remove the unsupported modules from the script.`	The script uses one or more unsupported SuiteScript modules: `N/http`, `N/https`, or `N/sftp`.
`Invalid call, the following required properties are missing: [parameter1, parameter2]`	Required parameters are missing.
`The script execution context creation failed due to the following issue: <error details>`	A critical error occurred during preparation, so the tool could not run.
`This tool is not allowed`	The tool needs a permission that the current session does not have.
`There was an unexpected error while executing the tool: <error details>`	The tool runs but fails on a line or throws an exception.
`Tool execution failed`	The tool does not return a result properly.

For additional examples, see common error messages in NetSuite Developer Tools.

How should you address an Access denied error?

Access denied. means the user’s role lacks access to the File Cabinet folder containing the tools. File access restrictions are applied to folders, not individual files. Review the enclosing folder rather than looking for a file-level restriction.

To change a folder’s restricted-access setting:

Log in with a role that has access to the folder.
Go to Documents > Files > File Cabinet.
Click Edit for the folder.
Select restrictions from the available lists for class, department, location, or group. List names can differ when record naming has been customized in the account.

Folder access can be restricted using criteria such as location and department. A private folder is available only to its creator and the account administrator. Administrators can view every folder, including private and restricted folders. A folder owner always has access regardless of restrictions.

For further context, see Credentials File Management in NetSuite 2026.1.

What should you check for restricted subfolders?

Subfolder timing matters when reviewing folder access. If a subfolder is created after its parent has been restricted to a group, the subfolder automatically inherits that parent restriction. The restriction can then be changed on the subfolder.

The reverse does not occur automatically. If a parent folder’s restriction changes after a subfolder already exists, the subfolder does not inherit the new restriction. Apply the restriction to the subfolder manually when needed.

A group restriction also has a timing consideration. When the selected group is dynamic, NetSuite restricts the folder to a snapshot of the dynamic group’s members for performance reasons. That snapshot is updated twice daily.

Which modules prevent a custom tool from loading?

A custom tool script cannot load the following SuiteScript modules:

N/http
N/https
N/sftp

When one or more of these modules are used, NetSuite displays the module-loading error and instructs you to remove the unsupported modules from the script. This is a loading issue: the tool cannot proceed while those unsupported modules are present.

For related development material, see N/error Module Members for SuiteScript 2.1 Development and enhanced execution logs for custom tool scripts.

How do the remaining errors narrow the problem?

The required-properties message identifies missing required parameters. The execution-context message means preparation encountered a critical error and prevented the tool from running. This tool is not allowed points to a permission the current session lacks.

The unexpected-execution message means the tool reached execution but failed on a line or threw an exception; the message includes error details. Tool execution failed is different: it indicates that the tool did not return a result properly. Keeping these stages separate prevents an access or module-loading issue from being treated as an execution failure.

Related resources include improved execution log support in NetSuite 2026.1 and standardized error codes in NetSuite bank imports.

Who This Affects

Users whose roles need access to File Cabinet folders containing custom tools.
Folder owners and account administrators who manage or review folder access.
Script authors whose custom tool scripts load SuiteScript modules or require parameters.
Users running tools in sessions that may not have a permission required by the tool.

Key Takeaways

Match the troubleshooting step to the exact tool error message.
Access denied. is tied to the user role’s access to the File Cabinet folder where the tools are located.
File Cabinet restrictions apply to folders, not individual files.
Existing subfolders do not automatically inherit a parent folder restriction changed later.
N/http, N/https, and N/sftp are unsupported in custom tool scripts.
Missing properties, execution-context failures, session permissions, execution exceptions, and improper results are separate error conditions.

NetSuite Custom Tool Error Messages Explained