Recompiling a VB.NET application

Question

So I have this VB.Net Application. It uses SQL Server database, for which it "hard-codes" the IP Address of the database inside its compiled code.

The server IP has changed and I can't start the software anymore. Also, I can't change the IP Address of the server (another server is using the same IP and it can't be changed).

It is just 2 EXE files with no external DLLs or anything else. So I opened both of them in HEX Editor, tried to search for the ascii of my IP address, but couldn't find it, tried also a HEX search but with no result.

Then I used .NET REFLECTOR ( http://www.red-gate.com/products/reflector/ ), and exported the code. I could see where the IP address is located: in Form2 a string variable named "strMyConnectionString". However, recompiling from the files exported by Reflector didn't work for me: I got 100 error and alot of warnings; obviously, the forms were missing but only their codes where decompiled. It has like 100 forms, and it is hard to redesign them (if that is even a considered a solution - not sure).

How do you suggest solving this? I need to change the IP as I can't use the software anymore!

Thanks!

Answer 1

You could try editing your local DNS settings . Open C:\\WINDOWS\\system32\\drivers\\etc\\hosts and specify a redirect from the old IP to the new one.

You could also try contacting the original author and requesting a new build.

If you authored it you should definitely not hard code changeable variables such as IP addresses and domain names :)

Answer 2

Instead of reflector, try ildasm

http://www.mactech.com/articles/mactech/Vol.19/19.12/NETbinaries/index.html

Answer 3

If you have a .NET exe that you don't have the source code for, you're going to need to brush up on Ildasm and Ilasm . Use Ildasm to covert the .EXE into Microsoft's Intermediate Language. Change the code there - it'll be in a text format, but the IL code will look more like assembly language than a 3GL. Once you've changed the IL, you can recompile to an .EXE with Ilasm. Yucky, but functional and probably your best choice without the original source.