diff --git a/components/fpspreadsheet/tests/internaltests.pas b/components/fpspreadsheet/tests/internaltests.pas
index d28c998d6..33994e031 100644
--- a/components/fpspreadsheet/tests/internaltests.pas
+++ b/components/fpspreadsheet/tests/internaltests.pas
@@ -34,7 +34,7 @@ type
     // Set up expected values:
     procedure SetUp; override;
     procedure TearDown; override;
-    procedure TestVirtualMode(AFormat: TsSpreadsheetFormat);
+    procedure TestVirtualMode(AFormat: TsSpreadsheetFormat; SaveMemoryMode: Boolean);
   published
     // Tests getting Excel style A1 cell locations from row/column based locations.
     // Bug 26447
@@ -55,12 +55,17 @@ type
     procedure TestVirtualMode_BIFF5;
     procedure TestVirtualMode_BIFF8;
     procedure TestVirtualMode_OOXML;
+
+    procedure TestVirtualMode_BIFF2_SaveMemory;
+    procedure TestVirtualMode_BIFF5_SaveMemory;
+    procedure TestVirtualMode_BIFF8_SaveMemory;
+    procedure TestVirtualMode_OOXML_SaveMemory;
   end;
 
 implementation
 
 uses
-  numberstests;
+  numberstests, stringtests;
 
 const
   InternalSheet = 'Internal'; //worksheet name
@@ -178,7 +183,9 @@ begin
   CheckEquals('$AA$2',GetCellString(1,26,[])); //just past the last letter
   CheckEquals('$GW$5',GetCellString(4,204,[])); //some big value
   CheckEquals('$IV$1',GetCellString(0,255,[])); //the last column of xls
+  CheckEquals('$IW$1',GetCellString(0,256,[])); //the first column beyond xls
   CheckEquals('$XFD$1',GetCellString(0,16383,[])); // the last column of xlsx
+  CheckEquals('$XFE$1',GetCellString(0,16384,[])); // the first column beyond xlsx
 
   // Something VERY big, beyond xlsx
   s := 'ZZZZ1';
@@ -199,18 +206,25 @@ end;
 procedure TSpreadInternalTests.NeedVirtualCellData(Sender: TObject;
   ARow, ACol: Cardinal; var AValue:Variant; var AStyleCell: PCell);
 begin
-  AValue := SollNumbers[ARow];
+  // First read the SollNumbers, then the first 4 SollStrings
+  // See comment in TestVirtualMode().
+  if ARow < Length(SollNumbers) then
+    AValue := SollNumbers[ARow]
+  else
+    AValue := SollStrings[ARow - Length(SollNumbers)];
 end;
 
-procedure TSpreadInternalTests.TestVirtualMode(AFormat: TsSpreadsheetFormat);
+procedure TSpreadInternalTests.TestVirtualMode(AFormat: TsSpreadsheetFormat;
+  SaveMemoryMode: Boolean);
 var
   tempFile: String;
   workbook: TsWorkbook;
   worksheet: TsWorksheet;
   row, col: Integer;
   value: Double;
+  s: String;
 begin
-  TempFile:=GetTempFileName;
+  TempFile := GetTempFileName;
   if FileExists(TempFile) then
     DeleteFile(TempFile);
 
@@ -218,10 +232,13 @@ begin
   try
     worksheet := workbook.AddWorksheet('VirtualMode');
     workbook.WritingOptions := workbook.WritingOptions + [woVirtualMode];
-    workbook.VirtualRowCount := Length(SollNumbers);
+    if SaveMemoryMode then
+      workbook.WritingOptions := workbook.WritingOptions + [woSaveMemory];
     workbook.VirtualColCount := 1;
+    workbook.VirtualRowCount := Length(SollNumbers) + 4;
+    // We'll use only the first 4 SollStrings, the others cause trouble due to utf8 and formatting.
     workbook.OnNeedCellData := @NeedVirtualCellData;
-    workbook.WriteToFile(tempfile, AFormat);
+    workbook.WriteToFile(tempfile, AFormat, true);
   finally
     workbook.Free;
   end;
@@ -232,13 +249,18 @@ begin
       workbook.ReadFromFile(tempFile, AFormat);
       worksheet := workbook.GetWorksheetByIndex(0);
       col := 0;
-      CheckEquals(Length(SollNumbers), worksheet.GetLastRowIndex+1,
+      CheckEquals(Length(SollNumbers) + 4, worksheet.GetLastRowIndex+1,
         'Row count mismatch');
-      for row := 0 to worksheet.GetLastRowIndex do begin
+      for row := 0 to Length(SollNumbers)-1 do begin
         value := worksheet.ReadAsNumber(row, col);
         CheckEquals(SollNumbers[row], value,
           'Test number value mismatch, cell '+CellNotation(workSheet, row, col))
       end;
+      for row := Length(SollNumbers) to worksheet.GetLastRowIndex do begin
+        s := worksheet.ReadAsUTF8Text(row, col);
+        CheckEquals(SollStrings[row - Length(SollNumbers)], s,
+          'Test string value mismatch, cell '+CellNotation(workSheet, row, col));
+      end;
     finally
       workbook.Free;
     end;
@@ -249,22 +271,42 @@ end;
 
 procedure TSpreadInternalTests.TestVirtualMode_BIFF2;
 begin
-  TestVirtualMode(sfExcel2);
+  TestVirtualMode(sfExcel2, false);
 end;
 
 procedure TSpreadInternalTests.TestVirtualMode_BIFF5;
 begin
-  TestVirtualMode(sfExcel5);
+  TestVirtualMode(sfExcel5, false);
 end;
 
 procedure TSpreadInternalTests.TestVirtualMode_BIFF8;
 begin
-  TestVirtualMode(sfExcel8);
+  TestVirtualMode(sfExcel8, false);
 end;
 
 procedure TSpreadInternalTests.TestVirtualMode_OOXML;
 begin
-  TestVirtualMode(sfOOXML);
+  TestVirtualMode(sfOOXML, false);
+end;
+
+procedure TSpreadInternalTests.TestVirtualMode_BIFF2_SaveMemory;
+begin
+  TestVirtualMode(sfExcel2, True);
+end;
+
+procedure TSpreadInternalTests.TestVirtualMode_BIFF5_SaveMemory;
+begin
+  TestVirtualMode(sfExcel5, true);
+end;
+
+procedure TSpreadInternalTests.TestVirtualMode_BIFF8_SaveMemory;
+begin
+  TestVirtualMode(sfExcel8, true);
+end;
+
+procedure TSpreadInternalTests.TestVirtualMode_OOXML_SaveMemory;
+begin
+  TestVirtualMode(sfOOXML, true);
 end;
 
 initialization
diff --git a/components/fpspreadsheet/tests/spreadtestgui.lpi b/components/fpspreadsheet/tests/spreadtestgui.lpi
index 1166ff9e0..cbbbad4a0 100644
--- a/components/fpspreadsheet/tests/spreadtestgui.lpi
+++ b/components/fpspreadsheet/tests/spreadtestgui.lpi
@@ -84,16 +84,15 @@
       <Unit2>
         <Filename Value="stringtests.pas"/>
         <IsPartOfProject Value="True"/>
+        <UnitName Value="stringtests"/>
       </Unit2>
       <Unit3>
         <Filename Value="numberstests.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="numberstests"/>
       </Unit3>
       <Unit4>
         <Filename Value="manualtests.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="manualtests"/>
       </Unit4>
       <Unit5>
         <Filename Value="testsutility.pas"/>
@@ -107,7 +106,6 @@
       <Unit7>
         <Filename Value="formattests.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="formattests"/>
       </Unit7>
       <Unit8>
         <Filename Value="colortests.pas"/>
@@ -128,7 +126,6 @@
       <Unit12>
         <Filename Value="rpnformulaunit.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="rpnFormulaUnit"/>
       </Unit12>
       <Unit13>
         <Filename Value="formulatests.pas"/>
@@ -138,7 +135,6 @@
       <Unit14>
         <Filename Value="emptycelltests.pas"/>
         <IsPartOfProject Value="True"/>
-        <UnitName Value="emptycelltests"/>
       </Unit14>
     </Units>
   </ProjectOptions>
diff --git a/components/fpspreadsheet/xlsbiff8.pas b/components/fpspreadsheet/xlsbiff8.pas
index bbf02277f..11f0b87af 100755
--- a/components/fpspreadsheet/xlsbiff8.pas
+++ b/components/fpspreadsheet/xlsbiff8.pas
@@ -364,7 +364,8 @@ var
   fn: String;
 begin
   if (woSaveMemory in Workbook.WritingOptions) then begin
-    fn := GetTempFileName;
+    fn := GetTempFileName('', 'fpsB8');
+    if FileExists(fn) then DeleteFile(fn);
     Stream := TFileStream.Create(fn, fmCreate + fmOpenRead)
   end else
     Stream := TMemoryStream.Create;
@@ -378,6 +379,8 @@ begin
 
     OutputStorage.WriteOLEFile(AFileName, OLEDocument, AOverwriteExisting, 'Workbook');
   finally
+    if (woSaveMemory in Workbook.WritingOptions) then
+      DeleteFile(fn);
     Stream.Free;
     OutputStorage.Free;
   end;