: Permissions issue with Windows Registry. Solution : Run the installer under the hidden Administrator account. Enable it via:
The installer will prompt you to choose a destination folder. refprop 91 install
Open Microsoft Excel (2007, 2010, 2013, 2016, or 2019). Go to File > Options > Add-ins . Look for “NIST REFPROP Add-in” under Active Application Add-ins. If not listed, manually load it via Browse and navigate to: : Permissions issue with Windows Registry
Go to File > Options > Trust Center > Trust Center Settings > Trusted Locations . Add your REFPROP folder (e.g., C:\Program Files\REFPROP ) and check "Subfolders of this location are also trusted". Open Microsoft Excel (2007, 2010, 2013, 2016, or 2019)
You must have the original installation files (usually an .exe installer or a folder containing SETUP.EXE ). 2. Step-by-Step Installation Process Step 1: Run the Installer