Attempted to read or write protected memory

By | July 31, 2020

The use of Sage 300 Advantage API is increasing day by day and there is an ample requirement of the integrations, import, export that uses it. Developers are now making maximum use of Advantage API compared to COMAPI and XAPI for external programs. XAPI requires separate licenses so end user tries to avoid an additional expense which eliminates the use of XAPI. When we create the utility with Advantage API, developer makes use of the classes and methods that are similar to the COMAPI or XAPI as it is handy.

New Stuff: Cannot access database (error=49153) in Sage 300 while accessing the Company

In this blog, we will be looking into an error generated by Sage 300 using Advantage API in C# .Net.

As a developer, we all are aware that CS Query/CS0120 View is most important and faster for reading data from Sage 300 tables. There can be situations where our program fails and it becomes difficult to identify the exact cause of the error by its description. So, debugging process makes it easier to track the line of code that throws an issue(s) if any. One of the reason for an error “Attempted to read or write protected memory. This is often an indication that other memory is corrupt.” is invalid use of “lockRecord” parameter passed to the function Fetch() of View object.

In our example of reading customer data using CS0120 view, we get an error when reading the data from the object whose Fetch() function has already returned true and we are inside our while loop.

While loop error

Below are the exception details displayed in QuickWatch.

Exception details in quickwatch

In order to get the program working and handling the issue, we need to change the lockRecord parameter to false i.e. customers.Fetch(false).

So, this can be helpful when the developer is stuck in the exception and becomes very cumbersome to track the cause. Developer/Programmer can proceed with their further development hassle free.

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