could any one please help me to solve this error?

error LNK2019: unresolved external symbol _Underst_Sql referenced in function _main 1>cartmot.obj :
error LNK2019: unresolved external symbol _Read_Desc referenced in function _main 1>cartmot.obj :
error LNK2019: unresolved external symbol _Assegna referenced in function _main
fatal error LNK1120: 3 unresolved externals

These are the linker errors I get when I compile my code

Please help me.

That error means those are either functions or objects that have been declared but not defined. A common cause is forgetting to give a body to one of your functions:

void function();

int main()
{
    function(); // error!
}

Another is including the headers for a library but forgetting to link to the library itself. Headers typically only contain declarations. I cannot tell you for sure what the problem is because I do not recognize those names.

That error means those are either functions or objects that have been declared but not defined. A common cause is forgetting to give a body to one of your functions:

void function();

int main()
{
    function(); // error!
}

Another is including the headers for a library but forgetting to link to the library itself. Headers typically only contain declarations. I cannot tell you for sure what the problem is because I do not recognize those names.

Yes the same three functions has been declared in the user defined header files. I have included the header files in the main program
How do fix these errors? I cannot modify the header files.

As you described above , they have declared the function in header files and called in tha main function. I do not have any idea about the library files. Would they have defined these functions in .obj files?

your above case does match with my problem. How do fix that error?

Thanks your reply Tomm

Static libraries are usually distributed as a *.h file and a *.lib file. Is this a third party library where you do not have the source? If so then there should be some compiled file along with the header that you can link to.

That error means those are either functions or objects that have been declared but not defined.

Thanks! I had this problem too, and saw this topic. What I quoted was the problem.

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