diff --git a/pyglossary/plugins/zimfile.py b/pyglossary/plugins/zimfile.py
index 7d744c5cc..a62a55ec9 100644
--- a/pyglossary/plugins/zimfile.py
+++ b/pyglossary/plugins/zimfile.py
@@ -124,8 +124,10 @@ def __iter__(self) -> "Iterator[EntryType | None]":  # noqa: PLR0912
 		try:
 			f_namemax = os.statvfs(cacheDir).f_namemax  # type: ignore
 		except AttributeError:
-			# FIXME
-			raise OSError("Unsupported operating system (no os.statvfs)") from None
+			log.warning("Unsupported operating system (no os.statvfs)")
+			# Windows: CreateFileA has a limit of 260 characters.
+			# CreateFileW supports names up to about 32760 characters (64kB).
+			f_namemax = 200
 
 		fileNameTooLong = []