wix 3.x - Failed to load xml file

Question

I have a WIX package - created using Wix Toolset 3.7, which is strangely failing on a specific environment with the following message,

ExecXmlFile: Error 0x80070005: failed to load XML file: \sharep001\share\IIS\pre\EAT\Website\CalculationService\Web.config

MSI (s) (70!FC) [11:15:37:491]: Product: EAT 1.0.0.0 -- Error 25531. Failed to open XML file \sharep001\share\IIS\pre\EAT\Website\CalculationService\Web.config, system error: -2147024891

Error 25531. Failed to open XML file \sharep001\share\IIS\pre\EAT\Website\CalculationService\Web.config, system error: -2147024891

CustomAction ExecXmlFile returned actual error code 1603 (note this may not be 100% accurate if translation happened inside sandbox)

Why I say the behavior is strange is because,

1. The same package I can install on the local directory on the webserver, no errors reported.
2. The same package I can install on another UNC directory, no errors reported.

Why is it failing? - The XML transform step only gets called after the directory is created, files are dropped, iis website is created, etc. So, hard to explain why, does not seem like a permission issue.

Any idea how I can debug this?

Answer 1

It is strange that the path does not contain a root drive specification. Is it possible that this file is on a different drive than where the custom action is executing and thus the relative path is not being found? I would first try to provide a full path to the file and see if that addresses the issue.

To debug, you could go hardcore and grab the sources and pdbs .zip files for the WiX toolset build you are using then use MsiBreak environment variable to get attached to the custom action .dll. From there, you can debug through the ExecXmlFile() function to see the actual return result. You could also inspect the machine just before/after the error occurs to see if the file is locked or otherwise inaccessible.

Good luck!

Answer 2

Check if file has correct UTF-8 encoding, my fault was a missing BOM Failed to open XML file , system error: -2147024786