The source file is differentfrom when the module was built. ASP.NET

Hi,
I have my project made from my pc and when I tried to open the solution from other computer, change the connectionStrings and run it. I'm receiving a message: The source file is different from when the module was built.  Would you like the debugger to use it anyway?
This appear when the program try to run my class, SqlHelper.vb. And when I select Yes, the program still uses the old SqlHelper.vb class (with the old connectionString).
Can someone help me to fix this?  I need to use the newer SqlHelper.vb.


Thanks in Advance!

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