diff --git a/docs/chameleonultragui.md b/docs/chameleonultragui.md
index b0e8b2be..4502df66 100644
--- a/docs/chameleonultragui.md
+++ b/docs/chameleonultragui.md
@@ -142,4 +142,9 @@ GDK_SCALE=2 GDK_DPI_SCALE=0.5 /usr/local/lib/chameleonultragui/chameleonultragui
 ### Key recovery from this card is not yet supported
 This error may occur when the card you are trying to recovery keys from is requiring a not yet supported recovery technology. You cannot tell the required recovery method from the outside.
 
-You may be able to solve this issue by dumping the card with a Proxmark3 or Mifare Classic Tool (Mobile App) and then importing a bin file.
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+You may be able to solve this issue by dumping the card with a Proxmark3 or Mifare Classic Tool (Mobile App) and then importing a bin file.
+
+### Error: Invalid data length
+This error may occur on windows devices and seems to be a deeper bug in the serial library.
+
+Reconnecting the device may solve it, also make sure that the App and Firmware are up to date.
\ No newline at end of file