diff --git a/main/HSSF/Record/TextObjectRecord.cs b/main/HSSF/Record/TextObjectRecord.cs
index a5594b3f3..f1958ceed 100644
--- a/main/HSSF/Record/TextObjectRecord.cs
+++ b/main/HSSF/Record/TextObjectRecord.cs
@@ -94,6 +94,9 @@ public TextObjectRecord(RecordInputStream in1)
                     throw new RecordFormatException("Read " + ptgs.Length
                             + " tokens but expected exactly 1");
                 }
+                if(!(ptgs[0] is OperandPtg)) {
+                    throw new ArgumentException("Had unexpected type of ptg at index 0: " + ptgs[0].GetType());
+                }
                 _linkRefPtg = (OperandPtg)ptgs[0];
                 if (in1.Remaining > 0)
                 {
diff --git a/testcases/ooxml/SS/Converter/TestExcelToHtmlConverterSuite.cs b/testcases/ooxml/SS/Converter/TestExcelToHtmlConverterSuite.cs
index 91c607418..40834c8e8 100644
--- a/testcases/ooxml/SS/Converter/TestExcelToHtmlConverterSuite.cs
+++ b/testcases/ooxml/SS/Converter/TestExcelToHtmlConverterSuite.cs
@@ -14,7 +14,7 @@ public class TestExcelToHtmlConverterSuite
         private static List<String> failingFiles = new List<string>();
 
         [Test]
-        [Ignore("test")]
+       
         public void TestExcelToHtmlConverter()
         {
             string[] fileNames = POIDataSamples.GetSpreadSheetInstance().GetFiles("*.xls");
@@ -22,7 +22,7 @@ public void TestExcelToHtmlConverter()
             StringBuilder stringBuilder = new StringBuilder();
             foreach (string filename in fileNames)
             {
-                if (filename.EndsWith(".xls"))
+                if (filename.EndsWith("clusterfuzz-testcase-minimized-POIHSSFFuzzer-6322470200934400.xls"))
                     toConverter.Add(filename);
                 else
                     continue;
diff --git a/testcases/test-data/spreadsheet/clusterfuzz-testcase-minimized-POIHSSFFuzzer-6322470200934400.xls b/testcases/test-data/spreadsheet/clusterfuzz-testcase-minimized-POIHSSFFuzzer-6322470200934400.xls
new file mode 100644
index 000000000..40f4ecaea
Binary files /dev/null and b/testcases/test-data/spreadsheet/clusterfuzz-testcase-minimized-POIHSSFFuzzer-6322470200934400.xls differ