diff --git a/packages/app-cli/tests/enex_to_md/resource_with_missing_encoding.enex b/packages/app-cli/tests/enex_to_md/resource_with_missing_encoding.enex
new file mode 100644
index 0000000000..25c0212ac3
--- /dev/null
+++ b/packages/app-cli/tests/enex_to_md/resource_with_missing_encoding.enex
@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE en-export SYSTEM "http://xml.evernote.com/pub/evernote-export4.dtd">
+<en-export export-date="20230724T173816Z" application="Evernote" version="10.58.8">
+<note>
+	<title>test.json</title>
+	<content><![CDATA[<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!DOCTYPE en-note SYSTEM "http://xml.evernote.com/pub/enml2.dtd">
+<en-note><en-media hash="ac91cc691d21261b222681dd38c1e4ad" type="application/json"/></en-note>
+]]>
+</content>
+<created>20191002T075850Z</created>
+<updated>20191002T075850Z</updated>
+<note-attributes><latitude>48.79547119140625</latitude><longitude>9.809423921920198</longitude><altitude>398.0</altitude><author>Laurent</author><source>desktop.mac</source></note-attributes>
+<resource><data>eyAidGVzdCI6IDEyMyB9</data><mime>application/json</mime><width>0</width><height>0</height><resource-attributes><file-name>test.json</file-name><attachment>false</attachment></resource-attributes></resource></note></en-export>
\ No newline at end of file
diff --git a/packages/lib/import-enex-md-gen.test.ts b/packages/lib/import-enex-md-gen.test.ts
index f2ff886ff1..a5e4062dfa 100644
--- a/packages/lib/import-enex-md-gen.test.ts
+++ b/packages/lib/import-enex-md-gen.test.ts
@@ -202,6 +202,18 @@ describe('import-enex-md-gen', () => {
 		expect(Resource.fullPath(resource).endsWith('.mscz')).toBe(true);
 	});
 
+	it('should handle resources without encoding', async () => {
+		// Handle case where the resource has a certain extension, eg. "mscz"
+		// and a mime type that doesn't really match (application/zip). In that
+		// case we want to make sure that the file is not converted to a .zip
+		// file. Fixes https://discourse.joplinapp.org/t/import-issue-evernote-enex-containing-musescore-file-mscz/31394/1
+		await importEnexFile('resource_with_missing_encoding.enex');
+		const resource = (await Resource.all())[0];
+		const resourcePath = Resource.fullPath(resource);
+		const content = await readFile(resourcePath, 'utf-8');
+		expect(content).toBe('{ "test": 123 }');
+	});
+
 	it('should sanitize resource filenames with slashes', async () => {
 		await importEnexFile('resource_filename_with_slashes.enex');
 		const resource: ResourceEntity = (await Resource.all())[0];
diff --git a/packages/lib/import-enex.ts b/packages/lib/import-enex.ts
index 5d19aa6e3d..fadf3cc731 100644
--- a/packages/lib/import-enex.ts
+++ b/packages/lib/import-enex.ts
@@ -150,12 +150,16 @@ async function processNoteResource(resource: ExtractedResource) {
 		// Some resources have no data, go figure, so we need a special case for this.
 		await handleNoDataResource(resource, true);
 	} else {
-		if (resource.dataEncoding === 'base64') {
+		// If encoding is not specified, it defaults to base64.
+		// Source: enex.dtd: <!ATTLIST data encoding (base64) "base64">
+		const dataEncoding = resource.dataEncoding ? resource.dataEncoding : 'base64';
+
+		if (dataEncoding === 'base64') {
 			const decodedFilePath = `${resource.dataFilePath}.decoded`;
 			await decodeBase64File(resource.dataFilePath, decodedFilePath);
 			resource.dataFilePath = decodedFilePath;
-		} else if (resource.dataEncoding) {
-			throw new Error(`Cannot decode resource with encoding: ${resource.dataEncoding}`);
+		} else if (dataEncoding) {
+			throw new Error(`Cannot decode resource with encoding: ${dataEncoding}`);
 		}
 
 		const stats = await shim.fsDriver().stat(resource.dataFilePath);
diff --git a/packages/tools/cspell/dictionary4.txt b/packages/tools/cspell/dictionary4.txt
index 9861c31ced..0cc94172c1 100644
--- a/packages/tools/cspell/dictionary4.txt
+++ b/packages/tools/cspell/dictionary4.txt
@@ -209,4 +209,5 @@ SPSSO
 IDPSSO
 nameid
 attrname
-dpkg
\ No newline at end of file
+dpkg
+ATTLIST
\ No newline at end of file