The wrapper message 'Failed to load script file' is not a complete diagnosis. If the accompanying exception says that a file cannot be found, start by comparing the path requested by the loader with the path that is actually available to the running client.
Trace one path from caller to package
Find the LoadScriptFile call for the affected window. Write down the final path after locale prefixes, feature flags and string concatenation. Then inspect the package or loose-file location that this particular client build loads. A file visible in an unpacked work folder is not evidence that the live package contains that file.
Window class/caller:
Requested script path:
Active locale/feature branch:
Package or loose-file source used at runtime:
Actual stored path and filename:
Revision/date of the deployed package:Check spelling, directory levels and case according to the actual pack loader. Determine whether a later package overrides an earlier file. Repack only the changed files using your own established toolchain, keep the previous package, and make sure the running client is the one you updated.
Separate path errors from script errors
If the loader now reaches the file but raises AttributeError, ImportError, NameError or KeyError, the original path problem may be resolved. Read the new traceback and investigate the next failure on its own. Creating an empty file with the missing name can merely move the failure into a later lookup.
Verification
Open the affected window on a clean client start. Save the requested path, the package revision and the relevant syserr lines. A useful fix report says which mismatch was corrected and which action now works.
Reference
A missing PopupDialog script discussion shows the path-related form of this error. This guide adds a caller-to-package trace rather than assuming that every client uses the same folder layout.
If you need help, post the loader call and a small package path listing, not the whole client.