diff --git a/src/archive/plugins/Iso9660ArchivePlugin.cxx b/src/archive/plugins/Iso9660ArchivePlugin.cxx
index e8c1d9c9d..b8a2a0d64 100644
--- a/src/archive/plugins/Iso9660ArchivePlugin.cxx
+++ b/src/archive/plugins/Iso9660ArchivePlugin.cxx
@@ -31,7 +31,7 @@ struct Iso9660 {
 	explicit Iso9660(Path path)
 		:iso(iso9660_open(path.c_str())) {
 		if (iso == nullptr)
-			throw FmtRuntimeError("Failed to open ISO9660 file {}",
+			throw FmtRuntimeError("Failed to open ISO9660 file {:?}",
 					      path);
 	}
 
@@ -223,7 +223,7 @@ Iso9660ArchiveFile::OpenStream(const char *pathname,
 {
 	auto statbuf = iso9660_ifs_stat_translate(iso->iso, pathname);
 	if (statbuf == nullptr)
-		throw FmtRuntimeError("not found in the ISO file: {}",
+		throw FmtRuntimeError("not found in the ISO file: {:?}",
 				      pathname);
 
 	const lsn_t lsn = statbuf->lsn;
diff --git a/src/config/File.cxx b/src/config/File.cxx
index 20bc08a3d..d3fb6846f 100644
--- a/src/config/File.cxx
+++ b/src/config/File.cxx
@@ -211,7 +211,7 @@ ReadConfigFile(ConfigData &config_data, BufferedReader &reader, Path directory)
 			ReadConfigBlock(config_data, reader, name, bo,
 					tokenizer);
 		} else {
-			throw FmtRuntimeError("unrecognized parameter: {}",
+			throw FmtRuntimeError("unrecognized parameter: {:?}",
 					      name);
 		}
 	}
@@ -222,7 +222,7 @@ ReadConfigFile(ConfigData &config_data, Path path)
 {
 	assert(!path.IsNull());
 
-	FmtDebug(config_file_domain, "loading file {}", path);
+	FmtDebug(config_file_domain, "loading file {:?}", path);
 
 	FileReader file(path);
 
@@ -231,7 +231,7 @@ ReadConfigFile(ConfigData &config_data, Path path)
 	try {
 		ReadConfigFile(config_data, reader, path.GetDirectoryName());
 	} catch (...) {
-		std::throw_with_nested(FmtRuntimeError("Error in {} line {}",
+		std::throw_with_nested(FmtRuntimeError("Error in {:?} line {}",
 						       path,
 						       reader.GetLineNumber()));
 	}
diff --git a/src/config/Path.cxx b/src/config/Path.cxx
index a10439ba9..b1377dc44 100644
--- a/src/config/Path.cxx
+++ b/src/config/Path.cxx
@@ -24,7 +24,7 @@ GetHome(const char *user)
 {
 	AllocatedPath result = GetHomeDir(user);
 	if (result.IsNull())
-		throw FmtRuntimeError("no such user: {}", user);
+		throw FmtRuntimeError("no such user: {:?}", user);
 
 	return result;
 }
@@ -91,7 +91,7 @@ ParsePath(const char *path)
 				/ AllocatedPath::FromUTF8Throw(rest);
 		}
 	} else if (!PathTraitsUTF8::IsAbsolute(path)) {
-		throw FmtRuntimeError("not an absolute path: {}", path);
+		throw FmtRuntimeError("not an absolute path: {:?}", path);
 	} else {
 #endif
 		return AllocatedPath::FromUTF8Throw(path);
diff --git a/src/decoder/Thread.cxx b/src/decoder/Thread.cxx
index 29d30c49f..5f11e7346 100644
--- a/src/decoder/Thread.cxx
+++ b/src/decoder/Thread.cxx
@@ -439,7 +439,7 @@ try {
 	if (!allocated.empty())
 		error_uri = allocated.c_str();
 
-	std::throw_with_nested(FmtRuntimeError("Failed to decode {}",
+	std::throw_with_nested(FmtRuntimeError("Failed to decode {:?}",
 					       error_uri));
 }