here is the screenshot of errors i've got while updating bitdefender free edition v10
Hi voldor and welcome to BitDefender Support Forum.
The MD5 error appears when:
1) you have a low-speed/unstable internet connection. The update packets might become corrupted.
2) the update server is over-loaded.
3) the update server is in the middle of updating process (new files are uploaded on them), in which case you might download a newer version and an older version of the same file which results in an error.
The solution is simple: either wait a few moments (sometimes the error is gone after a few seconds) and try again an update, either try another update server:
http://upgrade.bitdefender.com (default setting)
Last update has an error in file Civ5Mod.targets.
At line 117 pos 42 ->
Do you use a router for your internet connection?
Please reboot and try again. Thank you.