Database trial version - validation period

[gstylianou]

Good evening,

I have a database which i need to create code so that after the installation date of the database, then after 30 days the database must close automatically and ask for admin code. Unfortunately I am a beginner in vba so I can not write the code. I'll be grateful if any forum member can help

Thanks in advanced

Regards

George.

 

[AlexHedley]

How are you checking installation date?
You could write a date to a Table when first opened.
Then every subsequent open check the difference between Now() and that Date.
If it is 30 or more DoCmd.Quit or popup a Form for an Admin etc.

Are you creating this as a .accde so that the code can't be amended or adding other security?

 

[CJ_London]

And what is to stop the user changing the date in the table?

 

[NigelShaw]

Hey,

You might want check about forward clocking. If I downloaded it today, I could reset my PC for 30 yrs forward, install and then rest the time. I would then be in - days effectively giving me 30 yrs and 30 days before I need to register.....

There are some good security modules about. Sage key is my recommendation


Thanks

Nigel

 

[gstylianou]

Good morning from Cyprus

Fisrt of all i would like to thank everyone for your interest to help me. I believe this issue which I have posted will interest many of the members of our forum .

Well ,
Following is my oppinion in order to create the "Trial Version Vba Module" :

Step1: We must Create a table named «tblInstallation» which includes a field named "InstDate". In this datefield , only the Admin can have access in order to add the installation date of the database . It is understood that after updating the datefield, will be locked and only the Admin can make changes to it .

Step2 : The "tblInstallation" includes another date field which called "CurntDate" which takes the computer's current date which is usefull for the confirmation between the "InstDate" and the "CurntDate" every day . With this way we can create a Log file for the daily date.

Step3 : Once done the above then using vba code "On-Open Database" will compare the "InstDate" and "CurntDate" so if the date value of the "CurntDate" is before the "InstDate" ( eg InstDate = 1 / 1/14 and CurntDate = 30/12/13) then the database give an error message and then going immediately to quits . With this way we can ensure that in case where someone try to change the date on computer in order to trick the system, the database can not work . Please note that: We can take the current date value ("CurntDate") also through internet using vba code so to ensure the correct current date ().

In case where someone moved the date of the computer some years later than the date of installation, then the system will take into account the date of installation ("InstDate) and after to compares it with the time period that is specified as "Trial Period" ( eg 30 days ). Now, in case where the system recognize the computer's date after this period ("InstDate + "maxValue" of trial period) then should give again a relevant error message and will quit the database . Please note that: If we have for example "InstDate" = 01/01/2014 and "CurntDate" = 01/01/2020 because of someone has changed the current date of the PC in order to fool the system , then the code should take as maxValue of "CurntDate" the "InstDate" + 30 (trial period expired date).

Step4 : Importand is, the table «tblInstallation» should includes another number field ("RegDays"which is variable number field) which the Admin can specify the database "Trial Period". With this option, the administrator can easily determine the trial period of the database.

All the above are my oppinion in terms of creating a Vba Module for this purpose . Unfortunately, as I mentioned I don't have the required knowledge and experience in the field of vba programming in order to create that Vba Module. I would be appreciate if anyone friend from our forum is able to help. I believe that in case where somebody can help, this can be very helpfull for all forum members.

Finally, as I mentioned from the beginning my database is currently in the final stage of completion. It's an "mde" file for the moment and still waiting this vba module.

Thanks again all.

Regards,

George