diff --git a/src/dos/dos.cpp b/src/dos/dos.cpp
index a2f96f909..13df1876c 100644
--- a/src/dos/dos.cpp
+++ b/src/dos/dos.cpp
@@ -74,6 +74,9 @@ char * shiftjis_upcase(char * str) {
     return str;
 }
 
+static Bitu DOS_25Handler_Actual(bool fat32);
+static Bitu DOS_26Handler_Actual(bool fat32);
+
 unsigned char cpm_compat_mode = CPM_COMPAT_MSDOS5;
 
 bool dos_in_hma = true;
@@ -2025,6 +2028,17 @@ static Bitu DOS_21Handler(void) {
 				}
 				rsize=false;
 			}
+			else if (reg_al == 5 && reg_cx == 0xFFFF && (dos.version.major > 7 || (dos.version.major == 7 && dos.version.minor >= 10))) {
+				/* Windows 9x FAT32 extended disk read/write */
+				reg_al = reg_dl - 1; /* INT 25h AL 0=A: 1=B:   This interface DL 1=A: 2=B: */
+				if (reg_si & 1)
+					DOS_26Handler_Actual(true/*fat32*/); /* writing */
+				else
+					DOS_25Handler_Actual(true/*fat32*/); /* reading */
+
+				/* CF needs to be returned on stack or else it's lost */
+				CALLBACK_SCF(!!(reg_flags & FLAG_CF));
+			}
 			else {
 				LOG(LOG_DOSMISC,LOG_ERROR)("DOS:Unhandled call %02X al=%02X (MS-DOS 7.x function)",reg_ah,reg_al);
 				CALLBACK_SCF(true);
@@ -2100,194 +2114,235 @@ static Bitu DOS_27Handler(void) {
 	return CBRET_NONE;
 }
 
-static Bitu DOS_25Handler(void) {
+static Bitu DOS_25Handler_Actual(bool fat32) {
 	if (reg_al >= DOS_DRIVES || !Drives[reg_al] || Drives[reg_al]->isRemovable()) {
-        reg_ax = 0x8002;
-        SETFLAGBIT(CF,true);
-    } else {
-        DOS_Drive *drv = Drives[reg_al];
-        /* assume drv != NULL */
-        Bit32u sector_size = drv->GetSectorSize();
-        Bit32u sector_count = drv->GetSectorCount();
-        PhysPt ptr = PhysMake(SegValue(ds),reg_bx);
-        Bit32u req_count = reg_cx;
-        Bit32u sector_num = reg_dx;
+		reg_ax = 0x8002;
+		SETFLAGBIT(CF,true);
+	} else {
+		DOS_Drive *drv = Drives[reg_al];
+		/* assume drv != NULL */
+		Bit32u sector_size = drv->GetSectorSize();
+		Bit32u sector_count = drv->GetSectorCount();
+		PhysPt ptr = PhysMake(SegValue(ds),reg_bx);
+		Bit32u req_count = reg_cx;
+		Bit32u sector_num = reg_dx;
 
-        /* For < 32MB drives.
-         *  AL = drive
-         *  CX = sector count (not 0xFFFF)
-         *  DX = sector number
-         *  DS:BX = pointer to disk transfer area
-         *
-         * For >= 32MB drives.
-         *
-         *  AL = drive
-         *  CX = 0xFFFF
-         *  DS:BX = disk read packet
-         *
-         *  Disk read packet:
-         *    +0 DWORD = sector number
-         *    +4 WORD = sector count
-         *    +6 DWORD = disk tranfer area
-         */
-        if (sector_count != 0 && sector_size != 0) {
-            unsigned char tmp[2048];
-            const char *method;
+		/* For < 32MB drives.
+		 *  AL = drive
+		 *  CX = sector count (not 0xFFFF)
+		 *  DX = sector number
+		 *  DS:BX = pointer to disk transfer area
+		 *
+		 * For >= 32MB drives.
+		 *
+		 *  AL = drive
+		 *  CX = 0xFFFF
+		 *  DS:BX = disk read packet
+		 *
+		 *  Disk read packet:
+		 *    +0 DWORD = sector number
+		 *    +4 WORD = sector count
+		 *    +6 DWORD = disk tranfer area
+		 */
+		if (sector_count != 0 && sector_size != 0) {
+			unsigned char tmp[2048];
+			const char *method;
 
-            if (sector_size > sizeof(tmp)) {
-                reg_ax = 0x8002;
-                SETFLAGBIT(CF,true);
-                return CBRET_NONE;
-            }
+			if (sector_size > sizeof(tmp)) {
+				reg_ax = 0x8002;
+				SETFLAGBIT(CF,true);
+				return CBRET_NONE;
+			}
 
-            if (sector_count > 0xFFFF && req_count != 0xFFFF) {
-                reg_ax = 0x0207; // must use CX=0xFFFF API for > 64KB segment partitions
-                SETFLAGBIT(CF,true);
-                return CBRET_NONE;
-            }
+			if (sector_count > 0xFFFF && req_count != 0xFFFF) {
+				reg_ax = 0x0207; // must use CX=0xFFFF API for > 64KB segment partitions
+				SETFLAGBIT(CF,true);
+				return CBRET_NONE;
+			}
 
-            if (req_count == 0xFFFF) {
-                sector_num = mem_readd(ptr+0);
-                req_count = mem_readw(ptr+4);
-                Bit32u p = mem_readd(ptr+6);
-                ptr = PhysMake(p >> 16u,p & 0xFFFFu);
-                method = ">=32MB";
-            }
-            else {
-                method = "<32MB";
-            }
+			if (fat32) {
+				sector_num = mem_readd(ptr+0);
+				req_count = mem_readw(ptr+4);
+				Bit32u p = mem_readd(ptr+6);
+				ptr = PhysMake(p >> 16u,p & 0xFFFFu);
+				method = "Win95/FAT32";
+			}
+			else if (req_count == 0xFFFF) {
+				sector_num = mem_readd(ptr+0);
+				req_count = mem_readw(ptr+4);
+				Bit32u p = mem_readd(ptr+6);
+				ptr = PhysMake(p >> 16u,p & 0xFFFFu);
+				method = ">=32MB";
+			}
+			else {
+				method = "<32MB";
+			}
 
-            LOG(LOG_MISC,LOG_DEBUG)("INT 25h READ: sector=%lu count=%lu ptr=%lx method='%s'",
-                (unsigned long)sector_num,
-                (unsigned long)req_count,
-                (unsigned long)ptr,
-                method);
+			if (fat32) {
+				LOG(LOG_MISC,LOG_DEBUG)("INT 21h AX=7305h READ: sector=%lu count=%lu ptr=%lx method='%s'",
+						(unsigned long)sector_num,
+						(unsigned long)req_count,
+						(unsigned long)ptr,
+						method);
+			}
+			else {
+				LOG(LOG_MISC,LOG_DEBUG)("INT 25h READ: sector=%lu count=%lu ptr=%lx method='%s'",
+						(unsigned long)sector_num,
+						(unsigned long)req_count,
+						(unsigned long)ptr,
+						method);
+			}
 
-            SETFLAGBIT(CF,false);
-            reg_ax = 0;
+			SETFLAGBIT(CF,false);
+			reg_ax = 0;
 
-            while (req_count > 0) {
-                Bit8u res = drv->Read_AbsoluteSector_INT25(sector_num,tmp);
-                if (res != 0) {
-                    reg_ax = 0x8002;
-                    SETFLAGBIT(CF,true);
-                    break;
-                }
+			while (req_count > 0) {
+				Bit8u res = drv->Read_AbsoluteSector_INT25(sector_num,tmp);
+				if (res != 0) {
+					reg_ax = 0x8002;
+					SETFLAGBIT(CF,true);
+					break;
+				}
 
-                for (unsigned int i=0;i < (unsigned int)sector_size;i++)
-                    mem_writeb(ptr+i,tmp[i]);
+				for (unsigned int i=0;i < (unsigned int)sector_size;i++)
+					mem_writeb(ptr+i,tmp[i]);
 
-                req_count--;
-                sector_num++;
-                ptr += sector_size;
-            }
+				req_count--;
+				sector_num++;
+				ptr += sector_size;
+			}
 
-            return CBRET_NONE;
-        }
+			return CBRET_NONE;
+		}
 
-        /* MicroProse installer hack, inherited from DOSBox SVN, as a fallback if INT 25h emulation is not available for the drive. */
-        if (reg_cx == 1 && reg_dx == 0 && reg_al >= 2) {
-            // write some BPB data into buffer for MicroProse installers
-            mem_writew(ptr+0x1c,0x3f); // hidden sectors
-            SETFLAGBIT(CF,false);
-            reg_ax = 0;
-        } else {
-            LOG(LOG_DOSMISC,LOG_NORMAL)("int 25 called but not as disk detection drive %u",reg_al);
-            reg_ax = 0x8002;
-            SETFLAGBIT(CF,true);
-        }
-    }
-    return CBRET_NONE;
+		/* MicroProse installer hack, inherited from DOSBox SVN, as a fallback if INT 25h emulation is not available for the drive. */
+		if (reg_cx == 1 && reg_dx == 0 && reg_al >= 2) {
+			// write some BPB data into buffer for MicroProse installers
+			mem_writew(ptr+0x1c,0x3f); // hidden sectors
+			SETFLAGBIT(CF,false);
+			reg_ax = 0;
+		} else {
+			LOG(LOG_DOSMISC,LOG_NORMAL)("int 25 called but not as disk detection drive %u",reg_al);
+			reg_ax = 0x8002;
+			SETFLAGBIT(CF,true);
+		}
+	}
+	return CBRET_NONE;
 }
-static Bitu DOS_26Handler(void) {
+
+static Bitu DOS_25Handler(void) {
+	return DOS_25Handler_Actual(false);
+}
+
+static Bitu DOS_26Handler_Actual(bool fat32) {
 	if (reg_al >= DOS_DRIVES || !Drives[reg_al] || Drives[reg_al]->isRemovable()) {	
 		reg_ax = 0x8002;
 		SETFLAGBIT(CF,true);
-    } else {
-        DOS_Drive *drv = Drives[reg_al];
-        /* assume drv != NULL */
-        Bit32u sector_size = drv->GetSectorSize();
-        Bit32u sector_count = drv->GetSectorCount();
-        PhysPt ptr = PhysMake(SegValue(ds),reg_bx);
-        Bit32u req_count = reg_cx;
-        Bit32u sector_num = reg_dx;
+	} else {
+		DOS_Drive *drv = Drives[reg_al];
+		/* assume drv != NULL */
+		Bit32u sector_size = drv->GetSectorSize();
+		Bit32u sector_count = drv->GetSectorCount();
+		PhysPt ptr = PhysMake(SegValue(ds),reg_bx);
+		Bit32u req_count = reg_cx;
+		Bit32u sector_num = reg_dx;
 
-        /* For < 32MB drives.
-         *  AL = drive
-         *  CX = sector count (not 0xFFFF)
-         *  DX = sector number
-         *  DS:BX = pointer to disk transfer area
-         *
-         * For >= 32MB drives.
-         *
-         *  AL = drive
-         *  CX = 0xFFFF
-         *  DS:BX = disk read packet
-         *
-         *  Disk read packet:
-         *    +0 DWORD = sector number
-         *    +4 WORD = sector count
-         *    +6 DWORD = disk tranfer area
-         */
-        if (sector_count != 0 && sector_size != 0) {
-            unsigned char tmp[2048];
-            const char *method;
+		/* For < 32MB drives.
+		 *  AL = drive
+		 *  CX = sector count (not 0xFFFF)
+		 *  DX = sector number
+		 *  DS:BX = pointer to disk transfer area
+		 *
+		 * For >= 32MB drives.
+		 *
+		 *  AL = drive
+		 *  CX = 0xFFFF
+		 *  DS:BX = disk read packet
+		 *
+		 *  Disk read packet:
+		 *    +0 DWORD = sector number
+		 *    +4 WORD = sector count
+		 *    +6 DWORD = disk tranfer area
+		 */
+		if (sector_count != 0 && sector_size != 0) {
+			unsigned char tmp[2048];
+			const char *method;
 
-            if (sector_size > sizeof(tmp)) {
-                reg_ax = 0x8002;
-                SETFLAGBIT(CF,true);
-                return CBRET_NONE;
-            }
+			if (sector_size > sizeof(tmp)) {
+				reg_ax = 0x8002;
+				SETFLAGBIT(CF,true);
+				return CBRET_NONE;
+			}
 
-            if (sector_count > 0xFFFF && req_count != 0xFFFF) {
-                reg_ax = 0x0207; // must use CX=0xFFFF API for > 64KB segment partitions
-                SETFLAGBIT(CF,true);
-                return CBRET_NONE;
-            }
+			if (sector_count > 0xFFFF && req_count != 0xFFFF) {
+				reg_ax = 0x0207; // must use CX=0xFFFF API for > 64KB segment partitions
+				SETFLAGBIT(CF,true);
+				return CBRET_NONE;
+			}
 
-            if (req_count == 0xFFFF) {
-                sector_num = mem_readd(ptr+0);
-                req_count = mem_readw(ptr+4);
-                Bit32u p = mem_readd(ptr+6);
-                ptr = PhysMake(p >> 16u,p & 0xFFFFu);
-                method = ">=32MB";
-            }
-            else {
-                method = "<32MB";
-            }
+			if (fat32) {
+				sector_num = mem_readd(ptr+0);
+				req_count = mem_readw(ptr+4);
+				Bit32u p = mem_readd(ptr+6);
+				ptr = PhysMake(p >> 16u,p & 0xFFFFu);
+				method = "Win95/FAT32";
+			}
+			else if (req_count == 0xFFFF) {
+				sector_num = mem_readd(ptr+0);
+				req_count = mem_readw(ptr+4);
+				Bit32u p = mem_readd(ptr+6);
+				ptr = PhysMake(p >> 16u,p & 0xFFFFu);
+				method = ">=32MB";
+			}
+			else {
+				method = "<32MB";
+			}
 
-            LOG(LOG_MISC,LOG_DEBUG)("INT 26h WRITE: sector=%lu count=%lu ptr=%lx method='%s'",
-                (unsigned long)sector_num,
-                (unsigned long)req_count,
-                (unsigned long)ptr,
-                method);
+			if (fat32) {
+				LOG(LOG_MISC,LOG_DEBUG)("INT 21h AX=7305h WRITE: sector=%lu count=%lu ptr=%lx method='%s'",
+						(unsigned long)sector_num,
+						(unsigned long)req_count,
+						(unsigned long)ptr,
+						method);
+			}
+			else {
+				LOG(LOG_MISC,LOG_DEBUG)("INT 26h WRITE: sector=%lu count=%lu ptr=%lx method='%s'",
+						(unsigned long)sector_num,
+						(unsigned long)req_count,
+						(unsigned long)ptr,
+						method);
+			}
 
-            SETFLAGBIT(CF,false);
-            reg_ax = 0;
+			SETFLAGBIT(CF,false);
+			reg_ax = 0;
 
-            while (req_count > 0) {
-                for (unsigned int i=0;i < (unsigned int)sector_size;i++)
-                    tmp[i] = mem_readb(ptr+i);
+			while (req_count > 0) {
+				for (unsigned int i=0;i < (unsigned int)sector_size;i++)
+					tmp[i] = mem_readb(ptr+i);
 
-                Bit8u res = drv->Write_AbsoluteSector_INT25(sector_num,tmp);
-                if (res != 0) {
-                    reg_ax = 0x8002;
-                    SETFLAGBIT(CF,true);
-                    break;
-                }
+				Bit8u res = drv->Write_AbsoluteSector_INT25(sector_num,tmp);
+				if (res != 0) {
+					reg_ax = 0x8002;
+					SETFLAGBIT(CF,true);
+					break;
+				}
 
-                req_count--;
-                sector_num++;
-                ptr += sector_size;
-            }
+				req_count--;
+				sector_num++;
+				ptr += sector_size;
+			}
 
-            return CBRET_NONE;
-        }
+			return CBRET_NONE;
+		}
 
-        reg_ax = 0x8002;
-        SETFLAGBIT(CF,true);
-    }
-    return CBRET_NONE;
+		reg_ax = 0x8002;
+		SETFLAGBIT(CF,true);
+	}
+	return CBRET_NONE;
+}
+
+static Bitu DOS_26Handler(void) {
+	return DOS_26Handler_Actual(false);
 }
 
 bool enable_collating_uppercase = true;