diff --git a/poi-util/src/main/java/de/muehlencord/shared/poi/WorkbookApp.java b/poi-util/src/main/java/de/muehlencord/shared/poi/WorkbookApp.java
index d6b2769..71ff311 100644
--- a/poi-util/src/main/java/de/muehlencord/shared/poi/WorkbookApp.java
+++ b/poi-util/src/main/java/de/muehlencord/shared/poi/WorkbookApp.java
@@ -34,6 +34,7 @@ import org.apache.poi.ss.formula.ptg.Ptg;
 import org.apache.poi.ss.formula.ptg.RefPtgBase;
 import org.apache.poi.ss.usermodel.Cell;
 import org.apache.poi.ss.usermodel.CellStyle;
+import org.apache.poi.ss.usermodel.CellType;
 import org.apache.poi.ss.usermodel.DataValidation;
 import org.apache.poi.ss.usermodel.DataValidationHelper;
 import org.apache.poi.ss.usermodel.Row;
@@ -183,7 +184,7 @@ public class WorkbookApp {
                 newCell.setCellValue(oldCell.getNumericCellValue());
                 break;
             case BLANK:
-                newCell.setBlank();
+                newCell.setCellType(CellType.BLANK);
                 break;
             case BOOLEAN:
                 newCell.setCellValue(oldCell.getBooleanCellValue());
diff --git a/pom.xml b/pom.xml
index bf2bce1..d17945e 100644
--- a/pom.xml
+++ b/pom.xml
@@ -220,7 +220,8 @@ limitations under the License.
             <dependency>
                 <groupId>org.apache.poi</groupId>
                 <artifactId>poi-ooxml</artifactId>
-                <version>4.1.0</version>
+                <version>4.0.1</version>
+                <!-- do not upgrade to 4.1.0, see bug https://bz.apache.org/bugzilla/show_bug.cgi?id=63845 -->
             </dependency>  
             <dependency>
                 <groupId>com.inversoft</groupId>