Razvan's questions

I encounter the following error during Windows installation:

Setup cannot continue because a required file is either
corrupted or not available.  Run Setup again from the original
source disc or download location.

This error appears during the Installing Windows... phase, Expanding Windows files process.

The interesting part is that I only receive this while installing Windows from an USB flash drive with a capacity larger than 8 GB (I tried with 16GB and 64GB). The same image burned to a USB flash drive of 8GB works fine (no errors encountered).

Is there any such limitation when installing Windows from a flash drive?

Are there any ways to debug this further more, in order to understand what file/process is actually causing it?

There are a several utilities to run as a different user (eg: runas, cpau, psexec) but all of them require the password for the respective user, even if you are already running with elevated privileges.

I'd like to achieve the following:

1. I already have an elevated prompt (Administrator)
2. I'd like to execute a command (eg: calc.exe) as john without typing/passing their password to the launcher utility.

For example, in Unix system you could just:

root@server:~# su - john

I set up a Samba server on Ubuntu. Everything goes fine when I allow guest access, but when I try to setup a configuration for a specific user, I receive the error below:

$ smbclient  //x.x.x.x/john -U john
Enter john's password:
Domain=[MYDOMAIN] OS=[Unix] Server=[Samba 4.1.6-Ubuntu]
tree connect failed: NT_STATUS_ACCESS_DENIED

Here's the configuration on server side (/etc/samba/smb.conf):

[john]
    comment = Ubuntu File Server Share
    path = /home/john
    browsable = yes
    guest ok = yes
    read only = no
    create mask = 0755
    valid users = john
    writable = yes

Please note that:

• john account exists in /etc/passwd
• /home/john exists and it's owned by john:john
• as mentioned, the connection works fine when I allow guest access

It's the first time I do this. Am I missing something?

I want to forward the traffic from port 1111 to port 2222. So I execute the iptables command, but it seems that, somehow, the rule is not being saved.

# iptables -t nat -A PREROUTING -p tcp --dport 1111 -j REDIRECT --to-port 2222
# iptables -L -v
Chain INPUT (policy ACCEPT 24845 packets, 35M bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain OUTPUT (policy ACCEPT 24720 packets, 35M bytes)
 pkts bytes target     prot opt in     out     source               destination

I would expect that the iptables -L -v command would show the rule that I just created. It works for other rules but for this one it doesn't.

Am I missing something?

When I try to send an email (from a different server) to a local account on my server I get the following error:

Relaying denied. IP name possibly forged [W.X.Y.Z]

Here's what I do:

[email protected]:~$ telnet subdomain.domain.com 25
Trying A.B.C.D...
Connected to subdomain.domain.com.
Escape character is '^]'.
220 subdomain.domain.com ESMTP Sendmail 8.14.4/8.14.4/Debian-2ubuntu1; ...
HELO a-different-domain.com
250 subdomain.domain.com Hello ...
MAIL FROM: <[email protected]>
250 2.1.0 <[email protected]>... Sender ok
RCPT TO: <[email protected]>
550 5.7.1 <[email protected]>... Relaying denied. IP name possibly forged [W.X.Y.Z]

The problem is that I can send emails just fine if I use RCPT TO: <[email protected]> instead of RCPT TO: <[email protected]>

Please see below the configuration that I currently use.

DNS Configuration:

Host                 Type  Priority  Redirect to
subdomain.domain.com MX    10        mail.subdomain.domain.com
subdomain.domain.com A     10        A.B.C.D

Email server configuration:

OS: Ubuntu
Email Server: sendmail

In /etc/mail/access I have (among others):

mail.subdomain.domain.com
subdomain.domain.com

/etc/mail/local-host-names:

localhost
mail.subdomain.domain.com
subdomain.domain.com

Regarding the masquerading here is what I have in /etc/mail/sendmail.mc:

MASQUERADE_AS(`subdomain.domain.com')dnl
MASQUERADE_DOMAIN(`subdomain.domain.com.')dnl
MASQUERADE_DOMAIN(localhost)dnl
MASQUERADE_DOMAIN(localhost.localdomain)dnl

Just for clarifications: mail.subdomain.domain.com and subdomain.domain.com point to the same IP address.

================= UPDATE1 =================

@Andrzej A. Filip

Yes, i restarted sendmail.

Here is the output of echo '$=w' | sendmail -Am -bt:

root@subdomain:/etc/mail# echo '$=w' | sendmail -Am -bt
ADDRESS TEST MODE (ruleset 3 NOT automatically invoked)
Enter <ruleset> <address>
> [A.B.C.D]
mail.subdomain.domain.com
[ip6-loopback]
localhost
subdomain
ip6-localhost
[127.0.0.1]
[127.0.0.2]
subdomain.domain.com
[ip6-localhost]
ip6-loopback

================= UPDATE2 =================

I tested and found out (without changing the DNS configuration) that if i add subdomainXXX.domain.com (where subdomainXXX is any string) to /etc/mail/local-host-names and then I test sending an email from a remote server it simply works:

user@remote-server:/# telnet subdomain.domain.com 25
Trying A.B.C.D...
Connected to subdomain.domain.com.
Escape character is '^]'.
220 subdomain.domain.com ESMTP Sendmail 8.14.4/8.14.4/Debian-2ubuntu1; ...
HELO remote-server
250 subdomain.domain.com Hello ....
MAIL FROM: <...>
250 2.1.0 <...>... Sender ok
RCPT TO: <[email protected]>
250 2.1.5 <[email protected]>... Recipient ok

So it works for any subdomain except for the one that I'm interested into (subdomain.domain.com - which is actually the hostname of the server).