VB.NET has this rather annoying limitation which caps compiler warnings reported at 100.
vbc : warning BC42206: Maximum number of warnings has been exceeded.
You should read Configuring Warnings in Visual Basic and How to: Enable or Disable Compiler Warnings
For example, you can to the compiler options (under the project build properties) the following line
warnaserror:42206
this should (I haven't tried it myself...) disable your 100 errors limit.
On another note, 100 warnings is a very large number. You should probably go over your code, check and fix the reasons to those warnings.