# Security > Secure Windows Forms apps with TX Text Control: protected documents, untrusted files, PDF passwords, signing keys and a checklist for release. - **Product:** TX Text Control .NET for Windows Forms - **Section:** Documentation - **Kind:** Topic - **Path:** TX Text Control .NET for Windows Forms > Security - **875 words** - **Web URL:** https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/ - **LLMs URL:** https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/llms.txt - **LLMs-Full URL:** https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/llms-full.txt --- Security in a Windows Forms application with TX Text Control is about documents and the computer they're opened on. TX Text Control runs inside your application, on the user's computer, and offers protections that are part of the documents: restrictions for editing, passwords and permissions for PDF files and digital signatures. Your application decides who the user is, where passwords and certificates come from and what it installs. Developers who build such an application, and the people who review it, find here what each protection covers and where it ends. ### Where Security Applies - **In the editor.** Protected documents and editable regions decide what users of a `TextControl` may change. The user names they rely on come from your application. - **In the documents you open.** Documents from outside can be damaged, encrypted or full of links. Load settings, exceptions and events let your code decide what is imported and what a click opens. - **In the documents you hand out.** A user password encrypts a PDF, permissions restrict what readers do, and a digital signature makes changes detectable. - **In the files you ship.** The license agreement names files that must never be installed, and the private feed's credentials belong in no build output. ### Find the Right Page | If you want to | Read | |---|---| | Understand where documents are processed and what your application decides | [Security Overview](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/overview/llms-full.txt) | | Know what protected documents and editable regions guard against, and set user names safely | [Document Protection and User Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/document-protection/llms-full.txt) | | Open documents from other people without surprises | [Handling Untrusted Documents](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/untrusted-documents/llms-full.txt) | | Remove names or other text for good before a document is shared | [Redact Text](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/untrusted-documents/#redact-text) | | Encrypt PDF documents, respect the permissions of others and check the output | [PDF Passwords and Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/pdf-passwords/llms-full.txt) | | Decide where signing certificates and their private keys are kept | [Certificate and Private Key Handling](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/certificates/llms-full.txt) | | Check an application before it ships: files, credentials, isolation, updates and SBOMs | [Secure Application Deployment](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/deployment/llms-full.txt) | ### Where to Start 1. [Security Overview](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/overview/llms-full.txt): the model and the mechanisms at a glance. 2. The page for what your application does with documents: protecting them, opening them from outside, or creating encrypted or signed PDF documents. 3. [Secure Application Deployment](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/deployment/llms-full.txt) before the first release. The feature pages show how to use each mechanism: [Document Protection and Editable Regions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/document-editor/protection/llms-full.txt) for the editor, [Passwords and Access Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/pdf/passwords/llms-full.txt) for PDF files and [Digital Signatures](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/digital-signatures/llms-full.txt) for signing. ### Pages in This Section - [Security Overview](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/overview/llms-full.txt): where documents are processed and what TX Text Control and your application each provide. - [Document Protection and User Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/document-protection/llms-full.txt): the limits of document protection and how user names reach the editor. - [Handling Untrusted Documents](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/untrusted-documents/llms-full.txt): accepted formats, load errors, links, file references and text redaction. - [PDF Passwords and Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/pdf-passwords/llms-full.txt): what passwords and permissions protect, and how to apply and verify them. - [Certificate and Private Key Handling](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/certificates/llms-full.txt): where a signing key can live and who can sign with it. - [Secure Application Deployment](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/deployment/llms-full.txt): the checklist before your application ships. --- ## In This Section - [Certificate and Private Key Handling](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/certificates/llms-full.txt): Decide where signing keys live in a Windows Forms app: PFX files, the user certificate store or smart cards, and who can sign with a DigitalSignature. - [Secure Application Deployment](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/deployment/llms-full.txt): Release checklist for Windows Forms apps: files that must not ship, nuget.config API tokens, MSIX AppContainer isolation, service packs and signed SBOMs. - [Document Protection and User Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/document-protection/llms-full.txt): What EditMode, DocumentPermissions and editable regions prevent in Windows Forms, why UserNames needs your sign-in, and how MasterPassword unlocks files. - [Security Overview](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/overview/llms-full.txt): Where a Windows Forms app processes documents, what TextControl protection, PDF passwords and signatures cover, and what your own code must decide. - [PDF Passwords and Permissions](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/pdf-passwords/llms-full.txt): What PDF user and master passwords and DocumentAccessPermissions protect in a Windows Forms app, where permissions stop and what the app must enforce itself. - [Handling Untrusted Documents](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/untrusted-documents/llms-full.txt): Open received files in a Windows Forms TextControl: limit Open dialog formats, catch FilterException, check links in HypertextLinkClicked and redact text. --- ## Nearby - **Previous:** [CI/CD](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/deployment/ci-cd/llms-full.txt) - **Next:** [Security Overview](https://docs.textcontrol.com/tx-text-control-dotnet-winforms/security/overview/llms-full.txt)