A Guide To Potential Problems

Last Updated: 29th June 2003


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Introduction
While using IBrowse² it is not inconceivable that you may experience a problem with the software or web page you are viewing. This chapter has been put together to try and address some of these issues, in addition to covering some of the error messages you may experience.

JavaScript
Timeout Errors
When executing JavaScript on a web page, IBrowse² includes a safety feature in the form of a timeout. What this means is, if the JavaScript is extremely complex or even faulty (therefore resulting in a loop), after a predefined period of time IBrowse² will halt the execution and present you with a requester asking if you would like to continue or abort. As complex JavaScript can be rather CPU intensive, if you have a slow CPU these timeout requesters can appear frequently and seemingly for no apparent reason. This problem can be especially apparent if images are being decoded or SSL connections are being performed at the same time as the JavaScript execution. To stop this from happening as often, increase the value of the Preferences » Security » JavaScript time limit option.

Printing
TurboPrint 7 PreferencesPostScript Printing Via GhostScript & TurboPrint 7
Having followed the advice in the Printing chapter to configure IBrowse², TurboPrint 7.x, GhostScript & Workbench, IBrowse² will still not print and just silently does nothing. Newer versions of GhostScript (greater than v5.10 from IrseeSoft) require a larger buffer to operate correctly with, than previous versions. The recommended value to set Buffer kB to is 20480 (20MB) and can be configured in the PS tab of the TurboPrint preferences. If you do not have enough memory to set the buffer to this size, revert to an older version of GhostScript, such as the version supplied by IrseeSoft at http://www.irseesoft.de/ghostscript/default.htm.

SSL
Preferences » Security » Ciphers is disabled/ghosted.
Although IBrowse² supports both MiamiSSL and AmiSSLv2, in order to use this section of the IBrowse² preferences, AmiSSLv2 must be correctly installed. We recommend using AmiSSLv2 with IBrowse² as it is based on a later release of OpenSSL than MiamiSSL, and has various bugfixes not found in the last available release of MiamiSSL (which is now discontinued). It also integrates fully with IBrowse² allowing you to have more control over the SSL configuration. However, both MiamiSSL and AmiSSLv2 will work just fine with IBrowse².
I have AmiSSL installed, but it does not seem to work.
IBrowse² will only work with AmiSSLv2 (that is version 2) and is not compatible with AmiSSL (version 1). If you wish to use SSL with IBrowse² via the Genesis, AmiTCP or Roadshow TCP/IP stacks, you must install AmiSSLv2.
Where can I get AmiSSLv2 from ?
AmiSSLv2 is avilable to download from the IOSPIRIT website.
Secure sites are reporting 128bit security is required.
AmiSSLv2 and MiamiSSL both support 128bit cipher suites, but unfortunately some web page authors choose to detect certain browser capabilities to determine if they are able to support 128bit encryption. Usually this simply turns into a case of "which version of Netscape or Internet Explorer are you using ?" and if the browser reports something else, then you are assumed not to support suitable encryption levels and are directed to the usual "Please use a later version of Netscape or IE". Assuming you have MiamiSSL or AmiSSLv2 correctly installed, this can occasionally be cured by setting IBrowse² to report itself as Mozilla (a.k.a Netscape), using Preferences » URL cache » Spoof as Mozilla.

Should this error persist even after spoofing, it could be due to the web site requiring the use of a cipher which is disabled in Preferences » Security » Ciphers - try enabling all ciphers and then accessing the site again. In particular 3DES is often disabled due to the CPU intensive nature of the encryption, but some sites may check if this cipher is available as part of their browser detection routines.

Secure sites take a long time to load.
When communicating with a web server via SSL, each connection that is open puts load on not only the MODEM (if you use one), but also on the CPU, as it needs to process the data it receives, be it the communication processes with the server, the decoding of an image, or the handling of data encryption/decryption. The stronger the cipher suite that is used to transfer the data, the more load that is put onto the CPU, all of which means the web page that is loading can become very slow. There are a couple of steps that you can take in order to improve the loading times:
  • Reducing Preferences » Network » Max. number of secure connections will mean the CPU is not trying to process as much data at one time. This can help speed up the loading of the web page, as well as help with system responsivness if the system has become bogged down.
  • Disabling Preferences » Security » Ciphers » Encryption » 3DES. This form of encryption is a very complicated algorithm (3DES stands for Triple DES, so its 3 times as complex as the standard DES encryption), and as such puts a lot of load on the CPU. By disabling 3DES, IBrowse² will not report support for any cipher suites based on the 3DES encryption scheme, which means only cipher suites based on the slightly "softer" encryption schemes can be chosen.
Secure sites produce a handshake error.
There is a bug in the current release of AmiSSLv2 which on some systems can cause IBrowse² to either fail to connect to certain secure web sites, or fail to load images on secure web pages. The temporary fix for this is to disable Preferences » Security » SSLv2 support.

General
IBrowse² is using all of my RAM.
The majority of memory leaks present in IBrowse² v2.2 have been fixed in v2.3. However, there are some minor issues left but these should not cause all of your remaining RAM to be used. There are there areas that could affect memory usages, which although obvious, are often over looked:
IBrowse² takes forever to load.
IBrowse² loads and parses the Download Manager logfiles at startup which can cause a considerable delay if they are quite long. The following procedure will clear the logfiles, and optionally disable them entirely if you decide you have no use for them:
  • Open the Download Manager via the Menus » Windows » Download Manager menu entry.
  • Click on the Completed downloads tab.
  • Click on Remove all to purge the logfile.
  • Click on the Failed downloads tab.
  • Click on Remove all to purge the logfile.
Optionally stop the Download Manager creating logfiles in the future, as follows:
Some LZX archives are displayed by IBrowse²
IBrowse² determines how to handle various file types by the MIME Type that is assosiated with it. Although you may have an entry for LZX archives in Preferences » General » MIME Types, if the MIME Type set by the web server is not correct, IBrowse² will not know what to do with it, or will treat it as a different MIME Type. For cases such as this, IBrowse² can be forced to over ride the MIME Type supplied by the web server and instead match against the file extension, therefore treating archive.lzx correctly. The procedure for this is explained under Preferences » General » MIME Types » Extension

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IBrowse² Documentation v2.3 © 2002, 2003 Dave Fisher ~ IBrowse² Development Team Revision 1.0