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Articles

	avast! 6.x: Configuring the firewall application rules in avast! Internet Security
How to configure the firewall application rules in avast! Internet Security 6.x ? avast! Internet Security 6.x includes a fully integrated firewall which can be controlled directly from the avast! user interface, where you can also set the application rules governing the network and Internet communication for specific software applications. The firewall will then follow these rules whenever a particular application tries to establish a connection to the Int

	avast! 6.x: Installing and using the WebRep
What is the avast! WebRep? The WebRep is based on information received from the global avast! user community related to the content and security of visited websites, to help improve the browsing experience of all users. When you open your Web browser you will be able to see a reputation of every site you go to and whilst browsing through particular sites like popular search engines you will see that all the links are decorating with a color-coded mark that

	ADNM 4.x: Deployment of avast! Managed Client can fail on machines running Windows 7 or Vista
Issue avast! Distributed Network Manager 4.x (ADNM 4.x) can fail to deploy avast! Managed Client (NetClient) on remote machines running Microsoft Windows 7 or Microsoft Windows Vista operating systems. The remote install log can show the 'Access is denied' error messages. Details Windows 7 or Windows Vista operating system can prevent avast! Managed Client (NetClient) from being deployed remotely using the

	avast! 5.x: Video Tutorials
Are there any video tutorials available? If you are looking for a video tutorials demonstrating the basic steps when starting to use avast! 5.x products please visit the following page: http://support.avast.com/index.php?languageid=1&group=eng&_m=knowledgebase&_a=view&parentcategoryid=616 Conditions avast! Free Antivirus 5.x avast! Pro Antivirus 5.x avast! Internet Security 5.x Operating sys

	avast! 5.x: Configuring the firewall to allow VPN over IPsec in avast! Internet Security
Issue A VPN connection cannot be established over IPsec with the firewall enabled (running) in avast! Internet Security 5.0. Details In order to establish a VPN connection over IPsec through the firewall in avast! Internet Security 5.0, it is necessary that Encapsulating Security Payload (ESP) protocol and also Authentication Header (AH) protocol¹ (depending on VPN configuration) are defined in the packe

	avast! 5.x Web Shield may not scan HTTP traffic in some less common web browsers
Issue In some less commonly used web browsers, the Web Shield in avast! 5.x may not scan downloaded web content. Details avast! 5.x includes a Web Shield real-time scanning module able to monitor and filter HTTP traffic coming from Internet websites when using the most common web browsers such as Internet Explorer, Mozilla Firefox, Opera, Google Chrome, etc. Connections from the mentioned web browsers

	avast! 5.x: Configuring the firewall application rules in avast! Internet Security
How to configure the firewall application rules in avast! Internet Security 5.x ? avast! Internet Security 5.x includes a fully integrated firewall which can be controlled directly from the avast! user interface, where you can also set the application rules governing the network and Internet communication for specific software applications. The firewall will then follow these rules whenever a particular application tries to establish a connection to the Int

	'Web Shield' may not scan data traffic via some minority internet browsers
Issue If you use some minority internet browser (like Wyzo, etc.), avast! Web Shield may not scan its data traffic. Details avast! Web Shield acts as a transparent HTTP proxy and is compatible with major web browsers, including Microsoft Internet Explorer, Mozilla FireFox and Opera. If you experience described issue, your internet browser probably use differrent kind and non-standard access to the internet (e.g. bypassing transparent HTTP proxy, accessing directly to desired web pages, etc.).

	Error Message: '421 concurrent connections limit in avast exceeded'
Issue When the number of concurrent connections in avast! Internet Mail scanner is reached, you may recieve following error message: 421 concurrent connections limit in avast exceeded Details Limit of concurrent connections in avast! Internet Mail is common for all threads scanned by this provider - both e-mails (protocols SMTP, POP3 and IMAP) and news (protocol NNTP). This problem can be caused by any application capable of opening more concurrent connections using the protocols listed above

	Cannot change setting 'Never dial a connection' in 'Internet options'.
IssueAfter I installed avast!, my Internet options were set to Never dial a connection;, and whenever I change them, it comes back. What should I do?SolutionGo to the avast! Program settings... and define your Internet connection type (dial-up or permanent connection). It´s in Update (Connections) section.

	Required firewall settings to enable updates of Avast
What are the required firewall settings to enable updates of Avast Home and Professional Edition?Avast Home and Professional editions use http protocol port 80. Therefore this port must be open in your firewall.If you do not have an Internet connection you can carry out an offline update on our website in the section 'VPS updates'.More detailed information about the firewall settings for avast updates can be found in the following article in our knowledge base.

	Defining update addresses in the firewall settings
HOW TOConfigure the firewall to allow avast! to updateDESCRIPTIONSome firewalls (especially within companies) are configured to deny all traffic which is not on their list. This may cause a problem during an update of avast! antivirus. The servers used to update avast! antivirus are listed and continuously updated in the file C:\Program Files\Alwil Software\Avast4\Setup\servers.def therefore any change made to the file will not be effective. Servernames are represented by domain names (eg. download606.avast

	Web Shield and HTTP proxy
On my PC I am running another HTTP proxy (e.g. Proxomitron, WebWasher ...). It is listening on localhost and on port 3128 (or any other port). If I set-up 'Web Shield' to monitor the proxy port, and uncheck the "Ignore local communication" checkbox, it works correctly but I want Web Shield to scan downloads even before my HTTP proxy. Is this possible?Answer: Only processes that are known not to cause troubles are filtered by Web Shield. These include common browsers and many other tools already id

	ISP and HTTP proxy server
My ISP wants me to use their HTTP proxy server for accessing the Internet. In the Internet Explorer options dialog I can see my proxy server address is set as proxy.myisp.net, and the port as 3128 (or any other address/port details). How can I configure the 'Web Shield' to work in this situation? Answer: On NT-based system (Windows NT, 2000, XP, 2003)Right click the avast (a) icon in the taskbar. Choose "On-Access Protection Control" Find Web Shield in the provider list and click Customize. In the

	Win98/Me and 'Web Shield' does not seem to work
I use Win98/Me and 'Web Shield' does not seem to work. When I check the scanned count number on the Web Shield configuration page, it always shows 0. What can I do to solve this?Solution: Under Win98/ME you must configure your Web browser as if the transparent proxying is turned off. This is because the WebShield transparent proxy is not supported under this operating system. For detailed instructions, please see this FAQ entry.

	WebShield HTTP proxy
How do I manually configure the WebShield HTTP proxy? (e.g. because of ZoneAlarm Privacy Control or because running under Windows 95/98/ME)Answer: Under certain conditions, it is necessary to bypass the WebShield's transparent proxy and set things up manually. This includes the following situations: If you are using ZoneAlarm with Privacy Control turned on. The current version of WebShield's transparent proxy is incompatible with ZA's Privacy Control features. - OR - If you are using Windows 95/98/ME. WebSh

	Error message:
Whilst trying to update avast!, I get an error message stating: "Server is down". How can I resolve this problem?SolutionIf you see this error message whenever you try to update manually, check if: Your firewall allows avast! and its components to access the Internet (see also this FAQ) Your proxy server is set properly (SETTINGS -> UPDATE (BASIC) -> DETAILS -> PROXY -> SPECIFY PROXY SERVER)

	Update - (Connections)
I've been on dialup and have my avast! update connection is set to dialup-only. I intend to upgrade to DSL with a router. What's the difference, and the proper update setting for that situation?SolutionSetting: when using a dial-up connection, avast checks if there is an available connection each 30 seconds. If there isn't, it waits 30 more seconds and checks again. Setting: when using a permanent connection avast! pings the server at the time specified in avast4.ini file, and then each xx seconds looking f

	Update (Connections)
SymptomsI am running avast! Home edition on a Windows ME machine. Under Program Settings - Update (Connections) - I check the "I only connect to the internet using a dial-up modem" checkbox and say OK. When I go back into the settings the checkmark is gone. SolutionIf this happens, you can edit the [InetWD] section of the C:\Program Files\Alwil Software\Avast4\Data\avast4.ini file and add the following line if it doesn't exist already, if it does exist already, edit the value to =1:UseRAS=1 [I

	Only the option 'Abort connection' is available when avast! detects a virus
Issueavast! states it has found a virus, but it only offers me the choice Abort connection. Why can't I delete this virus?DetailsYou can't delete this virus as it's not actually on your computer. It is in fact somewhere on the net and was detected by one of the avast! resident providers - Web Shield. This provider scans all files that are downloaded via the Internet (HTTP protocol) before they're saved onto your local disk.SolutionThe only action that can be taken is to abort the connection and not allow th

	avast! and firewall software
What should I know about using avast! 4 in combination with a firewall?SolutionYou may receive warnings from your firewall once you install avast!, because avast! tries to connect to our servers to look for virus definition file updates and for program updates. It also acts as a transparent proxy. You should allow avast! to connect, otherwise the update feature will not work or your will not be able to browse internet websites. Here is some useful information: • The components of avast! 4 that should be all

	Web Shield and the 'AOL Browser'
IssueI use the AOL Browser for web browsing and reading emails via the AOL Web mail. Does avast! Web Shield work with this program? When I check the scanned count number on Web Shield configuration page, it always shows 0.ResultWe are sorry, but the Web Shield cannot scan connections from an AOL Browser. It is however capable of protecting standard browsers (Internet Explorer, Firefox, Opera, ...) used with an AOL dial-up or broadband services.

	Configuration of the Web Shield HTTP proxy
Issue How do I manually configure the Web Shield HTTP proxy? (e.g. because of ZoneAlarm Privacy Control or because running under Windows 95/98/ME) Details Under certain conditions, it is necessary to bypass the Web Shield's transparent proxy and set things up manually. This includes the following situations: If you are using ZoneAlarm with Privacy Control turned on. Zone Alarm's cookie blocking feauture currently does not work properly with WebShield's transparent proxy. Having both feat

	I can no longer browse the Web after avast! installation.
IssueI have installed avast! and I can no longer browse the Web. How can I solve this?SolutionCheck your firewall configuration. For the correct operation the Web Shield process (ashWebSv.exe or aswWebSv.exe) needs a permission to access the Internet on TCP port 80 and a permission to act as a server and accept incoming connections from localhost (the local machine) on TCP port 12080.

	Message: 'avast! Web Scanner (ashWebSv.exe) is trying to access the Internet'.
IssueAfter updating to version 4.6 my firewall warns me that avast! Web Scanner” (ashWebSv.exe) is trying to access the Internet. Is this correct?DetailsThis is correct. Web Shield provides all Web access for the browser. For it to work correctly you must allow this access in the Personal Firewall configuration.SolutionWeb Shield needs the same access rights as your browser - especially outgoing connection to the TCP port 80. If your firewall protects local communication you must also grant Web Shield proce

	Web Shield
What is Web Shield and how does it work?SolutionStarting from the version 4.6. avast! comes with a new on-access scanning provider - Web Shield. It is able to monitor and filter all HTTP traffic coming from the Web sites on the Internet. It’s implemented as a HTTP proxy running on your PC. Connections from your Web browser are redirected to the Web Shield module. Web Shield in turn connects to the requested web server and while downloading the content it scans it for viruses and Trojans. Only the clean data