'%3e%3cpath%20d='M8%200C12.4183%200%2016%203.58172%2016%208C16%2012.4183%2012.4183%2016%208%2016C3.58172%2016%200%2012.4183%200%208C0%203.58172%203.58172%200%208%200ZM11.6162%204.38379C11.2257%203.99337%2010.5927%203.99338%2010.2021%204.38379L8%206.58594L5.79785%204.38379C5.40732%203.99334%204.77429%203.99329%204.38379%204.38379C3.99331%204.77429%203.99335%205.40733%204.38379%205.79785L6.58594%208L4.38379%2010.2021C3.99348%2010.5927%203.99341%2011.2257%204.38379%2011.6162C4.77426%2012.0066%205.40734%2012.0065%205.79785%2011.6162L8%209.41406L10.2021%2011.6162C10.5927%2012.0066%2011.2257%2012.0067%2011.6162%2011.6162C12.0067%2011.2257%2012.0066%2010.5927%2011.6162%2010.2021L9.41406%208L11.6162%205.79785C12.0066%205.40735%2012.0066%204.77429%2011.6162%204.38379Z'%20fill='%23080E17'%20fill-opacity='0.46'/%3e%3c/g%3e%3cdefs%3e%3cclipPath%20id='clip0_3761_713'%3e%3crect%20width='16'%20height='16'%20fill='white'/%3e%3c/clipPath%3e%3c/defs%3e%3c/svg%3e)
Fix Data Streamer Certificate and Security Errors in Excel
Question details
Users encounter a security error indicating that the certificate used to sign the Data Streamer deployment manifest is not trusted.
- Product
- Microsoft Excel
- Device & OS
- Windows
- Scenario
- Installing or enabling the Data Streamer add-in from a downloaded archive.
- Observed behavior
- Excel blocks the add-in from loading and displays an error message stating the deployment manifest signing certificate is unavailable in the trusted store or not trusted.
Verify that your Windows system date and time are accurate, as an incorrect system clock can cause valid security certificates to appear expired or invalid.
Unblock the Downloaded Installer Archive
Windows automatically blocks files downloaded from the internet or other computers. Unblocking the archive before extracting it is the most effective way to resolve this security error.
When you download an installer package from another computer or network location, Windows applies a 'Mark of the Web' restriction to protect your PC. This prevents Excel from trusting the contents, including the deployment manifest.
You must remove this restriction before extracting the files to ensure the certificate is recognized properly.
Open File Explorer and navigate to the folder where the Data Streamer installer ZIP file is saved.
Right-click on the downloaded ZIP file and select 'Properties' from the context menu.
In the General tab, look at the bottom section for a Security warning. Check the box next to 'Unblock', then click 'Apply' and 'OK'.
Right-click the ZIP file again, select 'Extract All...', and run the installer from the newly extracted folder.
Import the Certificate to Trusted Publishers
If unblocking the file does not work, the signing certificate might need to be manually added to your computer's Trusted Publishers store.
Run Excel as an Administrator
Running Excel with administrative privileges can bypass certain local restriction policies preventing the add-in from initializing.
Try WPS Office for Seamless Spreadsheet Management
If you frequently encounter frustrating add-in certificate errors or compatibility blocks in Microsoft Excel, consider switching to WPS Office. It provides a lightweight, highly compatible spreadsheet tool that supports all major Excel formats seamlessly, without the heavy security overhead of legacy plugins.
- 1. Download the Installer: Visit the official WPS Office website and click the free download button to get the lightweight installer.
- 2. Install WPS Office: Run the installer file and follow the simple on-screen instructions to set up the software on your PC.
- 3. Open Your Spreadsheets: Launch WPS Spreadsheet and immediately open your existing .xlsx files to continue working seamlessly.
Frequently Asked Questions
Why does Windows block files downloaded from another computer?
Windows includes a security feature called 'Mark of the Web' (MotW) that flags files originating from the internet or other computers. This protects your system by prompting Office applications to block potentially unsafe active content, such as macros or add-in deployment manifests, until you explicitly unblock them.
What is the Excel Data Streamer add-in?
Data Streamer is an add-in for Microsoft Excel that allows users to stream real-time data from compatible microcontrollers (such as Arduino) or apps directly into Excel spreadsheets. It is widely used in educational settings for STEM projects and real-time data analysis.
How do I know if my system date and time are causing the certificate error?
Security certificates have strict validity periods (start and expiration dates). If your system clock is significantly incorrect (e.g., set to a year in the past or future), a perfectly valid certificate will be evaluated as expired or not yet valid. Right-click the time on your Windows taskbar, select 'Adjust date/time', and enable 'Set time automatically' to fix this.
