Note that, in order to uninstall a Bitnami stack, you must run the "uninstall.exe" executable inside each installation directory, not remove them:
If you already removed those directories and can't restore them from Windows' Recycle Bin, you must delete the services manually:
sc delete wampstackMySQL
sc delete wampstackMySQL-1
sc delete wampstackMySQL-2
sc delete wampstackApache
sc delete wampstackApache-1
sc delete wampstackApache-2
sc delete testlinkApache
sc delete testlinkMySQL
Once you have done that, you should be able to restore your installation.
NOTE: Run "serviceinstall.bat" and wait some seconds (until the window closes), before you run "serviceinstall.bat INSTALL".