Change of a level of protection against macro viruses

Since version Office 2000 there was such novelty: at attempt to start appendix Office containing macros, there is a message, offering to block «unsafe expressions». It is a question of the possible viruses containing in макросах and modules of the appendix.

Microsoft offers such variant of the decision of a problem (from Help):

• Carry out on a computer modern anti-virus programs
• Establish a high level of safety for macroowls
• Remove a tag To trust all established(installed) superstructures and patterns
• Use digital signatures; support(maintain) the list of the entrusted publishers. To change the list of reliable publishers of macroowls, on a computer the web-observer Microsoft Internet Explorer 5.01 with a package of updatings SP2 or later version should be established

In Office 2003 three levels of safety also are above applied:

High level

• Signed макрос – its processing is defined by its source and a condition of the signature
• Not signed макрос - macros are automatically disconnected. The file does not open

Average level

• Signed macros – its processing is defined by its source and a condition of the signature
• Not signed macros – the user is offered to open a database or to cancel action. If the user will decide to cancel action, the file of a database does not open

Low level

At a low level of safety all macros are processed equally, without dependence from their origin or the status of the certificate. At such level of safety the user is not offered to estimate reliability of the author or the certificate macros. Macros join automatically. This parameter should be used only if all макросы in files are received from reliable sources.

It was opinion Helpa. But here that occurs, after some reflection on this theme:

1. That all this system of certifications has earned, it is necessary to establish Microsoft Jet 4.0 Service Pack 8 or later version. In this case will be executed only макросы, having the special digital signature from «reliable manufacturers». Many developers, hardly when нибудь will take in head "to sign" the modules digital signatures. In the first, to hackers it hardly will strongly prevent to forge the signature, and in the second, this service paid, and the digital certificate can be received only in a commercial centre of certification, such as VeriSign Inc., or at the manager of internal security or the expert of a department of information technologies (IT)
2. If you have created the appendix for yourselves, and you are assured of yourselves, that will not create macro viruses can put a level of safety "Low" and easy work.
3. As, if you have created the distribution kit of the program at attempt to start it the user who has not replaced in advance a level of safety of macroowls, will have a message on impossibility of normal work with the program. As a variant – to offer the user the instruction, explaining where to come and what to switch. But such decision will seem to some your customers too complex. Not everyone wish to penetrate into such subtleties, it is necessary for the majority only that the program «normally worked».

The conclusion arises by itself – automat to switch blocking macroowls and to not take for a ride to itself and your clients. But here at once there is a problem: to disconnect blocking, it is necessary to start corresponding procedure, and start it we can only after start of the appendix which is blocked. Here to the aid will come VBS.

VBS is Microsoft Windows Script Technologies. Original alternative DOS .bat files. Scripts written on VBScript and kept as files with expansion .vbs are carried out by means of tool Windows Script Host (WSH) which is built in kernel Windows already from 98 versions.

Speaking is a usual text file easier, and it is created in a simple notebook, or in its more advanced variant – Bred or to whom that is pleasant more. After creation of a file, manually we change expansion on .vbs and all – the executed file is received. We shall click twice on it – compiler Windows will process the text and will give out result. Just as in .exe files. Besides, syntax VBS is very similar on VB of what you can be convinced hardly later, and accordingly, will not make the big work to understand a code.

So, we shall consider problems which should be solved:

1. To define version Access – in fact at installation Office 2003 way to the necessary parameter of the register (which should be changed) will be HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Access\security\Level and at installation Office 2007 - HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Access\Security\VBAWarnings
2. To lower a level of safety
3. To define a way to MSACCESS.EXE – it actually starts itself Access
4. To start the appendix

Take the base containing macros or modules and rename it in db1.mdb (or in a script change a name of base to yours). Create a folder for example С:/Prog and place in it a script and base. Open Access and through Service – Макрос – Safety establish a level of protection "High". Try to start the appendix – there will be a message on blocking. Now start a script double click – the appendix will open. Look, what now became a level of protection – low.

Example for given clause(article) you can below

The author: Admin Skript 2 кБ It is added: 27.04.2007