diff --git a/CHANGELOG.md b/CHANGELOG.md
index 11fd7f380..2a5055d81 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 - Updated Storage Drawers API (raoulvdberge)
 - Fixed bug where disks have to be re-inserted in the Disk Drive in order to work again after rejoining a chunk (raoulvdberge)
 - Fixed bug where items inserted in Storage Drawers through External Storage with a Drawer Controller wouldn't respect drawer priority rules (raoulvdberge)
+- Fixed crash on server when getting an advancement (raoulvdberge)
 - Autocrafting can now fill water bottles with water from the fluid storage - regular bottles or pattern for regular bottles are required (raoulvdberge)
 
 ### 1.5.7
diff --git a/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskFluid.java b/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskFluid.java
index b85e92d1d..0213e8030 100644
--- a/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskFluid.java
+++ b/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskFluid.java
@@ -227,7 +227,7 @@ public class StorageDiskFluid implements IStorageDisk<FluidStack> {
         this.accessType = accessType;
     }
 
-    public static NBTTagCompound getShareTag(NBTTagCompound tag) {
+    public static NBTTagCompound getShareTag(@Nullable NBTTagCompound tag) {
         NBTTagCompound otherTag = new NBTTagCompound();
 
         otherTag.setInteger(NBT_STORED, getStored(tag));
@@ -237,8 +237,8 @@ public class StorageDiskFluid implements IStorageDisk<FluidStack> {
         return otherTag;
     }
 
-    public static int getStored(NBTTagCompound tag) {
-        return tag.getInteger(NBT_STORED);
+    public static int getStored(@Nullable NBTTagCompound tag) {
+        return tag == null ? 0 : tag.getInteger(NBT_STORED);
     }
 
     public static NBTTagCompound getTag() {
diff --git a/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskItem.java b/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskItem.java
index 01fb588a0..a6c845f4e 100644
--- a/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskItem.java
+++ b/src/main/java/com/raoulvdberge/refinedstorage/apiimpl/storage/StorageDiskItem.java
@@ -281,7 +281,7 @@ public class StorageDiskItem implements IStorageDisk<ItemStack> {
         return inserted;
     }
 
-    public static NBTTagCompound getShareTag(NBTTagCompound tag) {
+    public static NBTTagCompound getShareTag(@Nullable NBTTagCompound tag) {
         NBTTagCompound otherTag = new NBTTagCompound();
 
         otherTag.setInteger(NBT_STORED, getStored(tag));
@@ -291,8 +291,8 @@ public class StorageDiskItem implements IStorageDisk<ItemStack> {
         return otherTag;
     }
 
-    public static int getStored(NBTTagCompound tag) {
-        return tag.getInteger(NBT_STORED);
+    public static int getStored(@Nullable NBTTagCompound tag) {
+        return tag == null ? 0 : tag.getInteger(NBT_STORED);
     }
 
     public static NBTTagCompound getTag() {