After the exectuion, some times only Output.mdb.zip, RawResults.zip and VuserLog.zip files created but sometimes after the execution, some more analysis files likewise- Results.zip, reports and HighLevelReport are also created.. What is the exact reason behind it ??

We found out that there is no option to open LoadRunner results file after opening the Analysis application. The only file type option available is .lra. Only way to open results file in analysis is to double click the results file. Any input would be great.