diff --git a/CHANGELOG.unreleased.md b/CHANGELOG.unreleased.md
index e8269c231..5abaf1001 100644
--- a/CHANGELOG.unreleased.md
+++ b/CHANGELOG.unreleased.md
@@ -7,6 +7,8 @@
 
 > Users must be able to say: “Nice enhancement, I'm eager to test it”
 
+- [VM import & Continuous Replication] Enable `guessVhdSizeOnImport` by default, this fix some `VDI_IO_ERROR` with XenServer 7.1 and XCP-ng 8.0 (PR [#4436](https://github.com/vatesfr/xen-orchestra/pull/4436))
+
 ### Bug fixes
 
 > Users must be able to say: “I had this issue, happy to know it's fixed”
diff --git a/packages/xo-server/config.toml b/packages/xo-server/config.toml
index 80a517490..e1d01fc52 100644
--- a/packages/xo-server/config.toml
+++ b/packages/xo-server/config.toml
@@ -17,9 +17,11 @@ createUserOnFirstSignin = true
 # their size just by looking at the beginning of the stream.
 #
 # But it is a guess, not a certainty, it depends on how the VHDs are formatted
-# by XenServer, therefore it's disabled for the moment but can be enabled
-# specifically for a user if necessary.
-guessVhdSizeOnImport = false
+# by XenServer.
+#
+# This has been tested for 5 months, therefore it's enabled by default but can
+# be disabled specifically for a user if necessary.
+guessVhdSizeOnImport = true
 
 # Whether API logs should contains the full request/response on
 # errors.