Outlook programming of an XRechnung tool for the Landesbetrieb LBB
Development of a customized Outlook add-in for the Landesbetrieb Liegenschafts- und Baubetreuung (LBB)
In mid-2021, Landesbetrieb LBB (Mainz) commissioned eWorks to develop a custom Outlook add-in to optimize its email workflow and the processing of e-invoices in XML data format (XRechnungen). Public authorities were already obliged to support XRechnungen at that time, which is why LBB wanted to have an intelligent Outlook add-in programmed for its team to simplify daily email traffic. To this end, LBB published a tender to find a certified Microsoft Outlook programmer, and the contract was ultimately awarded to eWorks.
The core function of the Outlook VBA solution developed is an automated processing workflow for XInvoices, which automatically processes all incoming e-mails with XInvoices including file attachments. The emails are first archived fully automatically in an audit-proof manner. They are then moved to the corresponding Outlook folders depending on their processing status, such as "XInvoice being processed", "XInvoice accepted" or "XInvoice rejected". This clear organization of all XInvoices simplifies invoice verification and, above all, prevents duplicate processing. Once the check has been completed, corresponding confirmations of receipt, defect lists or error messages are automatically generated from ready-made Outlook text modules.
Because users are generally not very familiar with XML data, additional VBA macros have been programmed to convert XInvoices into human-readable, "normal" invoices and display them as XHTML or PDF documents (which are generated from the XHTML documents). In this way, users can - just like before! - Xinvoices as PDF documents on the screen. And what pleases users also pleases the LBB: because the invoice verification process can be retained virtually unchanged for XRechnungen. As the proverbial icing on the cake, a few clever little helpers have been added to the Outlook VBA add-in, which automatically analyze the XML data of the XRechnungen and extract relevant information such as contact data and invoice numbers. This reduces the manual workload and eliminates potential sources of error.
In order to win the hearts of users, LBB also wanted to have even more advanced Outlook macros created that offer Outlook users useful convenience functions. These include, in particular, a repository for Outlook text modules with pre-formulated standard responses, checklists and pre-created Outlook forms that serve as templates and can be inserted into emails at the touch of a button. The Outlook text modules not only help to standardize, simplify and speed up e-mail correspondence, but also ensure consistent communication processes across the team. eWorks supported its client in creating Outlook text modules, but in future the client will expand and maintain the text modules independently and without technical support - as it is child's play and cost-efficient to do it yourself.
Technically, the Outlook add-in was programmed using Outlook VBA (short for "Visual Basic for Applications"), a proven and robust programming language from Microsoft that is used to automate tasks in Microsoft Office. (The alternative Microsoft .NET / C# was considered but rejected for various reasons). For XInvoice PDF generation, the Microsoft Edge web browser is used in so-called "headless" mode, which creates PDF documents without user interaction - which users can then view on screen, save, send, print or process in any other way. For the user interface, a separate menu ("ribbon") with graphically appealing buttons for the various Outlook VBA macros has been integrated into the familiar Outlook interface: the familiar Outlook look promises Outlook users an immediate recognition effect, quick familiarization and good acceptance. Thanks to the strong Edge and Outlook API, no commercial software licenses (e.g. from Adobe or other third-party providers) were required, which benefited the project costs. The saved project costs could instead be used to support both current industry standards "Cross Industry Invoice" (CII) and "Universal Business Language" (UBL).
Last but not least, the seamless integration of the developed Outlook add-in into the existing Outlook installations at the various government locations was on the agenda: a user-friendly location switch was programmed for this in order to manage location-specific configuration data such as e-mail addresses via convenient Outlook forms. The software is distributed via Windows group policies (GPO), which ensures fast and secure deployment even with large numbers of users. A file-based configuration mechanism was also programmed for content maintenance, which allows system administrators to make technical changes centrally and roll them out easily. In order to meet the client's high security requirements, all VBA macros in Outlook were digitally signed using a code signing certificate in accordance with the latest cryptographic standards.
After just a few months of planning, programming Outlook and quality assurance, the time had finally come: the LBB Outlook add-in saw the light of day. As part of the pilot tests, a few "change requests" (changes to requirements) were identified, reordered and programmed, and a short time later the final Outlook solution was put into productive operation. After the successful rollout, eWorks supports LBB in the long-term maintenance and further development of the Outlook add-in as part of demand-oriented support. The introduction of this Outlook add-in will not only make the LBB invoice verification process more efficient, but also more user-friendly for users.
The LBB Outlook add-in is a successful example of eWorks' ability to develop customized software solutions and integrate them seamlessly into existing systems, making users' day-to-day work noticeably easier through innovative automation.