UBUNTU - Installing Ubuntu packages causes FTP 550 Access Denied errors. Security ?

[CeesKrimp]

Running Plesk 11 on UBUNTU 12.04 TLS, based on iso from PLESK website, as Hyper-V VPS server. Plesk installation runs ok. Have installed the updates and upgraded using apt-get update and apt-get upgrade commands. Have created domain and email, all seems to run OK, except:

FTP to the domain gives FTP 550 Access Denied error, but I can FTP using just the IP-adress using root

Could this be related to security updates on Ubuntu? I have read some comments on better not doing any OS Upgrades. Is it recommended to turn of any auto updates/upgrades?

Currently rebuilding the Plesk server without the updates/upgrades as I have no idea how to backout the changes.

Any users using UBUNTU 12.04 TLS having the same experience; how do you deal with updates / upgrades on a server running Plesk?

 

[IgorG]

What is status of SELinux? Have you tried to disable it?

 

[CeesKrimp]

What is status of SELinux? Have you tried to disable it?

I checked the config and it appeared to be not turned on. Due to lack of time I had to start building new Plesk server, which I have done in the mean time.
Initially after completion on Plesk installation I also installed the outstanding updates/packages with apt-get update / upgrade; I ran into the same error.
I can FTP using the IP address and will nicely get into the home directory of the user, as soon as I log in using PLESK domain FTP accounts, it fails with the 550 error.
Decided to install new server without any updates/upgrades.

I installed a clean Ubuntu using the iso on the website and did not apply any updates/packages. Now it works again and I can FTP using Plesk FTP accounts.
May be related to SELinux, perhaps I did not properly check; will try to disable it.
I still have the failing Plesk server VPS on my server.

Is Parallels doing any regression tests with updates that are published on UBUNTU? Or is it advised not to run any upgrades at all?

I am a newbee to using Plesk Panels .. so any advise is appreciated.