diff --git a/CHANGELOG.unreleased.md b/CHANGELOG.unreleased.md
index 9c296820f74..a73a47ac34e 100644
--- a/CHANGELOG.unreleased.md
+++ b/CHANGELOG.unreleased.md
@@ -7,7 +7,7 @@
 
 > Users must be able to say: “Nice enhancement, I'm eager to test it”
 
-- [Ova export] speed up ova generation by 2. Generated file will be bigger ( as big as non compressed xva) (PR [#6487](https://github.com/vatesfr/xen-orchestra/pull/6487))
+- [OVA export] Speed up OVA generation by 2. Generated file will be bigger (as big as uncompressed XVA) (PR [#6487](https://github.com/vatesfr/xen-orchestra/pull/6487))
 
 ### Bug fixes
 
diff --git a/packages/xo-vmdk-to-vhd/src/index.js b/packages/xo-vmdk-to-vhd/src/index.js
index 164476cb18d..294fb910206 100644
--- a/packages/xo-vmdk-to-vhd/src/index.js
+++ b/packages/xo-vmdk-to-vhd/src/index.js
@@ -46,13 +46,13 @@ export async function computeVmdkLength(diskName, vhdReadStream) {
 export async function vhdToVMDK(diskName, vhdReadStreamGetter, withLength = false) {
   const { iterator, size } = await vhdToVMDKIterator(diskName, await vhdReadStreamGetter())
   let length
-  if (size === undefined) {
-    length = await computeVmdkLength(diskName, await vhdReadStreamGetter())
-  } else {
-    length = size
-  }
   const stream = await asyncIteratorToStream(iterator)
-  if (withLength) {
+  if(withLength){
+    if (size === undefined) {
+      length = await computeVmdkLength(diskName, await vhdReadStreamGetter())
+    } else {
+      length = size
+    }
     stream.length = length
   }
   return stream
diff --git a/packages/xo-vmdk-to-vhd/src/vmdk-generate.js b/packages/xo-vmdk-to-vhd/src/vmdk-generate.js
index 7db9526cad9..e4774149517 100644
--- a/packages/xo-vmdk-to-vhd/src/vmdk-generate.js
+++ b/packages/xo-vmdk-to-vhd/src/vmdk-generate.js
@@ -169,7 +169,7 @@ ddb.geometry.cylinders = "${geometry.cylinders}"
     remaining -= SECTOR_SIZE // MARKER_EOS
 
     if (remaining < 0) {
-      throw new Error('vmdk is smaller than precalculed size ')
+      throw new Error('vmdk is bigger than precalculed size ')
     }
     const size = 1024 * 1024
     while (remaining > 0) {