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Questions and Answers from the Computing Help Desk

  Collected by the IT/User Support Team

This is a collection of Questions & Answers that have been treated by the Computing Help Desk managed by the User Support group.

N.B. The number in parenthesis refers to problem registration at URL
where NNNN is the problem identifier (number).

Some PC "Tips"   -   (Hannes Schwarzbauer IT/User Support)

Question   - M/S "Windows" symbol   (0081)

I have a modern PC keyboard which has a key with the M/S "Windows" symbol on it. It is beneath the 'space' and 'alt' key. What is it good for?

Answer   -   It is a 'program function' or 'shortcut' key, which lets you rapidly execute some program or call up some functions.

Note that this key is NOT available on all standard keyboards.

Here is a list of available functions:

 Win Key (WK) :
 WK + E          Open/Ouvrir [Explorer]
 WK + R          Open/Ouvrir [command Run]
 WK + Pause      Open/Ouvrir [System Properties]
 WK + F          Display/Afficher [Find: All Files]
 WK + Ctrl + F   Display/Afficher [Find : Computer]
 WK + M          Minimize/Minimiser active windows
 WK + Shift + M  Discard/Annuler Minimize active windows
 WK + Tab        Go through/Circuler dans la Barre de Tâches [task bar]
 WK + F1 ou F1   Display/Afficher [Help Windows]


Question   - Error messages from Doctor Watson   (0084)
When I launch various PC applications, I keep getting error messages from Doctor Watson. What does this mean? Who is this doctor?

Answer   -   Dr. Watson is a problem report generator that kicks in when an application does something really bad. In general it means troubles, like memory problems.

If the user is running a standard NICE PC, the only reason for this to happen is a hardware problem. It can be anything from a faulty memory card to a dead processor fan with the heat rising on the motherboard.

If "rechecking everything" fails, the next option is to reinstall the system. If even this fails, it definitely is a hardware problem and the user must contact his normal PC support team, or the original supplier (for example the IT PC Desktop Service if the PC was originally purchased there).


Question   - passwords   (0103)
I have changed my password but it only works on W95, not on NT. Aren't they synchronised? The error message I get is: "Your password change request HAS NOT been processed because of an internal error. Please try again later."

Answer   -   This happens when a user's password is too long. It can be considered as a 'bug' in NT. NT only allows a maximum of 15 characters. The user must not use more than this maximum.


Question   - "Application log file full"   (0105)
Under Windows NT, I get the message: "Application log file full" What can I do?

Answer   -   This log is part of the NT event viewer. To clear it, go from 'programs' into 'administrative tools', then 'event viewer'. Before you clear the log and to be on the safe side, save the old one as whatever you want (e.g. oldfile).

Note: You have to be logged as Administrator to do this.


Question   - Automatically Adjust Clock   (0092)
If you are on a network which operating system has the functionality of adjusting for changes in daylight savings time, there will be a problem if you also use the Automatically Adjust Clock for Daylight Savings Time Changes feature in Windows 95, particularly if all workstations on the network are either not using Windows 95 or have disabled this feature in Control Panel, Date/Time, Time Zone tab.

If you allow the network operating system as well as Windows 95 to adjust for these changes, then you are no longer synchronized with the rest of the network and entries made into other users' schedules will be changed to try to adjust for this.

The following is an example of a Schedule+ problem that has been encountered: a Windows 95 user used Schedule+ to schedule meetings on a Novell network, running Windows 95 and Office 95. The other workstations are running Windows for Workgroups. The network operating system had adjusted all clocks on the system when there was a change between daylight saving time and eastern standard time. When the Windows 95 user was asked if he or she wanted to have Windows 95 automatically adjust for changing the clocks, the user chose "Yes". After this, all other schedules on the network that had meetings scheduled, prior to the time change, for 1:00 P.M. found that the time has now been changed to 2:00 P.M.

Explanation: if the network operating system adjusts the time and then Windows 95 adjusts the time, the Windows 95 machine is no longer synchronized with the other machines on the network. It has actually had its time set back by one hour twice. The workstation appears to be in a different time zone than the rest of the machines. In an effort to synchronize the times, the scheduled appointment times change.

Answer   -   To avoid this problem, choose Date/Time from the Control Panel. In the Time Zone tab, disable Automatically adjust clock for daylight savings time changes.

More information : If you click the question mark (?) on Automatically adjust clock for daylight savings time changes, you get an explanation of the feature as well as the following warning: If you use more than one operating system, make sure that only one of then adjusts for daylight saving time.

See also the question on AFS clock skew on UNIX.


Registry Settings -

N.B. The two following questions ("Deactivate screen saver" and "'pagefile.sys' file") imply manipulations of the registry; please note that USERS MUST UNDERSTAND WHAT they do before changing any value! (Or undesired side effects - that maybe difficult to debug even by the NICE experts - may occur afterwards).

Question   - Deactivate screen saver   (0087)
When a password protected screen saver starts, is it possible to get some grace period before a password needs to be entered to deactivate?

Answer   -   Yes it is. Although not set by default in NICE, this can be changed as follows:

 1. Start the registry editor (regedit.exe)
 2. Move to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows
    (or Windows NT)\CurrentVersion\Winlogon
 3. From the edit menu select New - String Value 
 4. Enter a name of ScreenSaverGracePeriod and press Enter
 5. Double click and set to the number of seconds grace period.
    Click ok.
 6. Close the registry editor
 7. Reboot the machine

Question   - 'pagefile.sys' file   (0093)
I have recently ran short on disk space on my hard drive on NT. By inspecting files I discovered a huge (in my case over 40MB) file called 'pagefile.sys'. Is it possible to safely delete or at least shrink this file?

Answer   -   During an NT session, it is not possible to access or open this system file. However, it can be shrunk/cleaned by this procedure:

Note: If this key doesn't exist, you have to create it:
Value Name: ClearPageFileAtShutdown
Value type: REG_DWORD
Value: 1

You have to reboot your NT machine after these changes.

N.B.: On an extremely full hard drive, it may be necessary to reduce the virtual memory size to a value less than the drive space available:

- Control panel - system - performance - virtual memory.

Some Unix "Tips"   -   (Nicole Crémel and Roger Woolnough IT/User Support)

Question   - AFS Cache   (0086)
When listing the directory content on 2 different nodes of the ATLAS server I got 2 different versions (one missing the latest corrections):

   atlas03 > rsh atlas02 ll
   -rw-r--r--   1 pop        zp           13390 Mar 26 14:06
   atlas03 > rsh atlas03 ll
   -rw-r--r--   1 pop        zp           13197 Mar 21 19:41
What can be done?

Answer   -   You can rectify this abnormal situation with the command "fs flush" which forces the AFS Cache Manager to remove each specified directory or file from its cache of data and status information. The result is that the next time data from a flushed directory or file is requested, the Cache Manager contacts the File Server for the most current version, along with a new callback (if necessary) and associated status information. This command does not discard data from application program buffers or data that has been altered in the cache but not yet written back to the central copy maintained by the File Server.

You can get all details regarding this AFS command with "man fs_flush".


Question   - Work Group Server   (0094)
Where to get all information (responsible, user guide, configuration details, performance reports, etc.) on a specific Work Group Server ? (e.g. THWGS, CMS, ATLAS, ALICE, CHORUS, NA48, NA49, TIS.)

Answer   -   See URL
It will give you links, name of "Local" and "IT" contact person, and the mailing list corresponding to the Work Group Server for all experiments.


Question   - fs sysname   (0097)
On RSPLUS the 2 commands "fs sysname" and "uname -r" (or "uname -a") give different information:

 [rsplus11] ~ > fs sysname
 Current sysname is 'rs_aix42'
 [rsplus11] ~ > uname -r
 [rsplus11] ~ > uname -a
 AIX rsplus11 3 4 001520FD4C00
(for AIX 4.3).

Why ?

Answer   -   The AFS "sysname" command is a relatively ad hoc constructions used basically to discriminate between different AFS binaries. It is used because it is automatically translated from "@sys" when used in an AFS path. However the exact "system release" is effectively given by the UNIX command "uname -r".


Question   - StarOffice (Word, Excel and Powerpoint)   (0100)
I would like to use the utility StarOffice, is it available at CERN through AFS ?

Answer   -   We know that many users are interested by this product which contains Word , Excel and Powerpoint 97 look-alikes. CERN is currently negotiating to have a site-wide licence and expects to have something in place shortly.

N.B. First versions will be for Solaris and Linux. Both Word and Excel utilities are fairly well compatable with the PC/Mac versions but the Powerpoint version is not able to re-transfer files from Linux/Solaris back to PC or Mac, although it can read them. In the future there maybe versions available for HP but not until end 1999 at earliest.


Question   - 'AFS clock skew' problem   (0102)
I installed the Transarc AFS client for NT and wanted to get an AFS token afterwards with afs_auth.exe but I got the following error message:

  "server and client clocks are badly skewed."
I use GMT+1:00 for the time zone. Do you know how to solve this problem?

Answer   -   The 'AFS clock skew' problem has been seen elsewhere on several occasions, fortunately in all cases it has come down to the same quirk in Windows/NT setup:

See also the question on Automatically Adjust Clock for PCs.

Some DeskTop Publishing "Tips"   -   (Andreas Wagner IT/User Support)

Question   - Print national characters   (0101)
I would like to print a text file containing national characters ?
When using xprint I only get strange symbols, what should I do ?

Answer   -   You can use a2ps to print such files, eg:

a2ps -P 513-us filename

xprint is converting text files to postscript by using internally an older version of a2ps. This version doesn't handle national characters properly. It is planned to update xprint in the future.



Question   - escape key on NCD terminal   (0088)
I'm using a NCD terminal, and there is at least one key (escape) that doesn't work properly. I don't mean that the key is mechanically bad, it just does not do what is supposed to do. How do I fix it?

Answer   -   If you have no pure "Esc" key and have F11 key labeled also (Esc) you can assign "Esc" value to this key just issuing command:

xmodmap -e "keysym F11 = Escape"

Then put this command in some startup rc-file.


Question   - Ethernet address   (0091)
What is the "Ethernet address" of a machine and how to find it?

Answer   -   The ethernet address is 12 hexadecimal (0-9, A-F) digits, of which the first six specify the maker of the interface and the last six are unique. On some systems this address is already printed on a label, either outside the system or inside on the interface card which has the network connector.

On a PC running Windows 95 there is normally a Control Panel program (menu Start - Settings - Control Panel) called "TCP/IP". Executing this shows a window giving the IP address and name, plus a small icon labelled "View Details". Clicking on this small icon should then give a second window including a field called Adapter Address, which specifies the ethernet Adapter Address.

For a PC running NT it is necessary first to open a Command Prompt window. On a NICE NT PC this is in "PROGRAMS" in the START menu. The command "wntipcfg" will then normally give the same window as for the Windows 95 PC, including the ethernet Adapter Address. If this "wntipcfg" command is unknown (perhaps because the NT is stand-alone) an alternative command is "net config work", which will produce a line like

 Workstation active on           NetBT_IEEPRO1 (Adapter Address)

On Unix systems the address is indicated at boot time. It may also be possible to run one of the following commands
  'netstat -i'          (on IBM AIX and DEC : needs the interface running!)
   '/usr/sbin/lscfg -v'  (on AIX)
   'dmesg"               (on Linux and Solaris : normally in /usr/sbin)
   'lanscan'             (on HP/UX : normally in /usr/sbin)

For a PC running Linux the ethernet address is written at startup time into a log file: normally /var/log/syslog or /var/log/messages.

On a recent Macintosh there is a Control Panel program called "TCPIP". Executing this shows a window giving the IP address. When this is visible there is an item in the "File" menu called "Show Info". Using this will normally give a separate window showing the ethernet address. If it does not then you have an old version of what is now called "Open Transport" To update choose the File Server "Srv0_Nice" in zone "NOVELL", select log on method "Apple Standard UAMs", enter as Guest, go into the Folder "Applications", then the Folder "System Tools", then the Folder "Universal System", then the Folder "OT 1.1.2-NET Install" and then double click on "Open Transport Installation".

Older Macintoshes have in the Control Panel a program called MacTCP. Executing this should show a window including an icon called "Ethernet". Holding down the "Option" key while clicking on this icon should then show the ethernet address. Note that this "Option" is sometimes marked "alt" and may have a little diagram on it like


The network team at CERN needs to know the exact ethernet address for a number of reasons. Primarily, it enables them to detect if someone else tries to "borrow" and use the corresponding IP address. In addition, it may happen that they detect hardware or software problems related to the ethernet address and wish to inform the owner and/or responsible person. The information is particularly valuable for systems registered as portable and not necessarily having a fixed home network socket or IP name and address.

If you are working at CERN you should be able to check all the networking parameters of your device (and eventually inform the network team of any wrong or missing information) by using the web form:


Question   - LHC++   (0098)
What are the definition for LHC++ software both at CERN and from outside, and especially the AFS availability?

Answer   -  

Everything is explained in the LHC++ Web page at URL:

Regarding access from AFS (root directory /afs/ anyone from a cern node can have general access. From an outside node, only the person who was designated to be in the cern:li group when registering can have access to the software. And in this case, only to the export tree: /afs/ for exporting the software off-site. The policy is not to allow direct use from afs for off-site. To see who is in the cern:li group type "pts mem cern:li".


Question   - Java programming language   (0104)
Who can I contact at CERN for questions/problems with the Java programming language?

Answer   -   There is no official support for Java but we invite users to address their questions/problems to the newsgroup.

This newsgroup is intended to be the most basic communication channel for the community of Java developers at CERN. In order not to restrict the immediate evolution the scope is initially quite wide:

We expect to structure the newsgroup (*) in a consensual way as needs arise and different elements of the Java infrastructure settle down. Also, no alternative communication mechanism is discarded (creation of a Java Users group, etc..) as long as it is convenient for the community and there is consensus to establish it.


Question   - Web access with AFS files   (0110)
I would like to restrict read access to certain web pages, and have protected them as far as the access via the web is concerned. The files themselves are on AFS.

How can I make them accessible to the server, but protect them from being read by other AFS users?

Answer   -   For the three servers, and it can be done via AFS group names in a "generic" way.

Example: If you want to restrict AFS read access to one of your home directories, just type

fs setacl mydirname webserver:home read


For matters related to this article please contact the author.

Last Updated on June 25th, 1999 at 15:43:10
Copyright © CERN 1999 -- European Laboratory for Particle Physics