> For the complete documentation index, see [llms.txt](https://kb.logicerp.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kb.logicerp.com/logic-erp-learning-hub-tutorials-and-best-practices/user-access/logic-global-admin/purchase/do-not-allow-date-change-of-transacted-purchase.md). # Do Not Allow Date Change of Transacted Purchase **YouTube:** [How to Prevent Voucher Date Changes in Purchase If Transactions Already Exist?](https://www.youtube.com/watch?v=GdifJ9BJMBE) ## How to Prevent Voucher Date Changes in Purchase If Transactions Already Exist? This tutorial explains how to enable a setting in **Logic ERP** that prevents users from changing the date of a **transacted purchase voucher**, enhancing data consistency and audit control. *** ### **Step-by-Step Configuration:** * Open the **Logic Folder** and run **Logic Admin**. * Go to **Global Settings**. * Navigate to the **Purchase** tab. * Locate and enable the option: **“Do Not Allow Date Change of Transacted Purchase”**

Let's keep this feature enable to observe its impact in Purchase.

* Click **Save** to apply the changes. * Restart the **Logic ERP** software to activate the new setting. *** ### **Effect of This Configuration** * When a user attempts to **modify the bill date** in a purchase voucher that has already been transacted (i.e., the items have been sold or used in another transaction), the system will block the action. * An error message will appear stating:\ \&#xNAN;**“**Transactions exist for this purchase voucher.... Cannot allow date change**.”**

This picture illustrates that the system blocks bill date changes if transactions exist, showing:
"Transactions exist... Cannot allow date change."

*** ### **Purpose** * This restriction ensures data integrity by preventing changes to dates in purchase vouchers that are already linked to subsequent transactions, such as sales or stock transfers. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://kb.logicerp.com/logic-erp-learning-hub-tutorials-and-best-practices/user-access/logic-global-admin/purchase/do-not-allow-date-change-of-transacted-purchase.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.