|This post is an FYI that may help others that have had similar problems.|
None of the browsers (IE6, Firefox Portable 2, Opera 7.54) on the problem computer (Dell 4600, Pentium-4/2.8 GHz, 512 MB RAM, WinXP/SP1), will bring up psu.edu (homepage), all giving error saying that they can not find the site or server. No browser problems noted with accessing any other websites normally used. Computer is on home LAN with Verizon DSL service/modem, network connection switch, and network mini-hub. None of the 3 other computers on the LAN, running Win98SE, Win2000/SP4, and WinXP/SP2, have any problems accessing psu.edu. The computer running WinXP/SP2 is essentially identical to the problem computer in terms of hardware and applications software configurations.
Saw an Internet page which referred to setting TCP/IP properties and compared the problem computer's TCP/IP properties configuration with another similar computer on the LAN, and noted that there were differences.
Needed to reset how Windows gets Internet DNS addresses, then had no problems accessing psu.edu again on all browsers.
Access from Control Panel - Network Connections - Local Area Connection icon - Properties - Internet Protocol (TCP/IP) - Properties - General tab. Changed checked option from "Use the following DNS server address" to "Obtain DNS address automatically". This is now the same configuration which is now on the other similar computer on the LAN which has no problems. When the original option was set in the past, there were some addresses (numbers not noted for this record) entered in the "Preferred DNS server" and "Alternate DNS server" entries, but these numbers disappeared when the option was unchecked.
Possible problem explanation:
Computer has been used during the last 3 academic years at PSU (Penn State/University Park), and had to be set to use specific DNS addresses to connect to the school network while in the dorms, and when the computer was moved home for the summer, this configuration was not changed.
Computer user said that there had been intermittent access problems to psu.edu for about a month at home, but in recent weeks access was no longer possible. During troubleshooting efforts below, access returned for a few minutes, but disappeared after computer was taken off LAN briefly and then reconnected.
The user later mentioned that a recent PSU August E-mail noted that for the dorm network access the TCP/IP properties should be set to "Obtain DNS address automatically", which is a change from previous years, when it was necessary to use the "Use the following DNS server address" option and input some DNS numbers given by PSU. It's possible they made some changes in recent weeks and that made the computer original configuration no longer valid in terms of how Windows get DNS addresses for some of PSU sites (including the homepage).
Troubleshooting item tried (not necessarily in order below):
- Was able to use command line programs PING and TRACERT to establish that the computer can in fact see/connect to psu.edu through the home LAN. PATHPING had connection problem and returned with error for finding psu.edu, but had no problems connecting to any other sites tested.
- Could access with browsers some PSU webpages which had additional identifiers in from of the psu.edu address (e.g. math.psu.edu), but not others (e.g. engr.psu.edu).
A Google search of the Internet turned up numerous webpages where others described similar problems (including someone with a georgetown.edu access problem!) and tried various measures. Some of the mentioned possible solutions were tested as per the list below, but with no success for re-establishing psu.edu access. Other possible causes of the problem such as the ISP provider blocking certain websites, or the website is down, or LAN hardware (e.g. router configuration) problem, etc. were obviously not relevant in this case since other different type of computers and a similar computer on the LAN had no access problems.
- Checked HOST and LMHOSTS.SAM files located in \windows\system32\drivers\etc\.
- Added psu.edu homepage DNS to HOST file.
- Using Crap Cleaner program, custom batch file, and manually, cleaned out all Internet cookies, caches, temporary Internet files from all browsers, \windows\temp, temp folders in Documents & Settings for all accounts, Recycle Bin.
- In Safe Mode with Networking, same problem with psu.edu access, but no problems with other websites tested.
- Turned off WinXP firewall.
- Checked whether any browser using proxy servers.
- Checked Control Panel - Internet Options - Security - Restricted Sites.
- Using DrTCP program, varied TCP/IP MTU setting from normally used 1492 value, and TCP Window value from normally used 8192
- LSPFix Winsock repair program.
- Did full computer scans using Symantec AV, AdAware, Spybot S&D (all with lastest definitions), Blacklight anti-rookit, SystemsInternals Rootkit Revealer, MS malware removal tool (Jul 06 version).
- Tried using IPCONFIG with /flushdns, /renew, /registerdns options.