How can Testers Resolve 'Invalid' Bugs?

Testers, after testing send bug report to the developers only to get 50 percent of them back after being labeled as "invalid". This happens only due to the incomplete testing setup by the testers.

Insufficient troubleshooting is the main cause of the bug which is being marked as invalid by the developers. With the help of troubleshooting, testers can decide whether the ambiguity they found is in the application under test as a bug or a test setup mishap.

Before reporting bugs what are the things that testers have to look out for:
At what point is the application not working?" This one question is more than sufficient to track bugs. While testing, testers have to make sure that there are no mistakes on their end before they report bugs. To resolve bugs a tester should be able to provide all possible solutions, efficiency & the drawbacks of each & every solution.

Here are some of the reasons for failure:
A tester using any configuration files for testing applications has to make sure that the file is up to date as per the application requirements. Always testers have to check whether the database is proper? sometimes missing table in the application can be the main reason for not working properly. Debug twice if tester is working on any automation testing project before concluding that the bug is because of an application failure and also testers have to check that - not to use invalid access credentials for authentication.

Before testing any application testers have to take care of:
A Tester have to check whether the software versions are compatible or if there is any hardware issues i.e., not related to the applications. The prerequisites of hardware & software have to be correct. On the test machine all the software components has to be installed properly and testers also have to make sure that all the latest software versions has been uploaded are related to the testing environment.