# Cannot lock pdf

**URL:** <https://pdfjs.community/t/cannot-lock-pdf/740>\
**Category:** Technical Support\
**Tags:** pdfjs-express\
**Created:** [April 30, 2021, 2:04pm UTC](https://pdfjs.community/t/cannot-lock-pdf/740 "2021-04-30T14:04:35Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![system](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/1X/ffbcd25c7d423db8d5acd5db201c272f4db306dd.png) [@system](https://pdfjs.community/u/system)\
**Post date:** [April 30, 2021, 2:04pm UTC](https://pdfjs.community/t/cannot-lock-pdf/740/2 "2021-04-30T14:04:41Z")

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**Hello, I’m Ron, an automated tech support bot 🤖**

While you wait for one of our customer support representatives to get back to you, please check out some of these documentation pages:

Guides:
- [Add signature fields to PDFs - createSignHereElement](https://pdfjs.express/documentation/signature/signature-field#createsignhereelement)
- [Why is the viewer showing “Network Failure”?](https://pdfjs.express/documentation/get-started/electron/viewer-showing-network-failure)
- [Customize toolbar in viewer - Examples - Add a custom save button](https://pdfjs.express/documentation/ui-customization/customizing-header#add-a-custom-save-button)

APIs:
- [Annotations - setCustomSerializeHandler(annotationClass, serializeHandler)](https://pdfjs.express/api/Annotations.html#.setCustomSerializeHandler__anchor)
- [Annotations.Forms.Field - new Field(name [, options])](https://pdfjs.express/api/Annotations.Forms.Field.html#Field__anchor)
- [PartRetrievers.LocalPdfPartRetriever](https://pdfjs.express/api/PartRetrievers.LocalPdfPartRetriever.html#__anchor)

Forums:
- [Adding custom information on shapes and custom items](https://pdfjs.community/t/adding-custom-information-on-shapes-and-custom-items/486/1)
- [How can we rotate pdf right/left from our custom buttons](https://pdfjs.community/t/how-can-we-rotate-pdf-right-left-from-our-custom-buttons/65/1)
- [Getting error log on loading a particular pdf](https://pdfjs.community/t/getting-error-log-on-loading-a-particular-pdf/564/9)

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_[View the full topic](https://pdfjs.community/t/cannot-lock-pdf/740)._