Unable to connect to my mail server.

SO, this was working before ?

1) DId you disable your firewall on your computer ?
2) Did you delete the connection doc and then try to open the server using - file- database- open, and using the correct IP address ?

3) Did you delete the cache.ndk file ?

I hope this helps !

Notes Uses Port 1532 make sure that this port is open on your firewall.. Ping uses a completely different port.  Just because you can ping does not mean port 1532 is open

Try opening a DOS window and typing

Telnet ServerNameOrServerIP 1352

If you get a boring black screen with no error message you were able to telnet to the server using that port

I am able to telnet. Interesting thing is that I uninstalled r7 and installed again in notes\data folder and it is working fine now. Able to connect to my mail server. Earlier I installed Lotus Notes in r7 folder. Any suggestion.

The only thing that I can think of is that your Notes.ini file was not pointing at the R7 Folder.  Not knowing what type of install you did perhaps you did not have a pointer to the correct ID file which would have caused you to not be able to authenticate with the server.  It would be perfectly feasible to do an install where you actually created an ID file out of thin air that had no relationship to the organization at all.  Sometimes you have old outdated ID files on a machine..

There can be multiple causes..  I always like to put the ID file in the Address book temporarily and have the user put in the connection information when they do the setup.  It makes it slightly easier to see where the cockups are occuring..   The most complicated thing about notes is that it uses double key encryption on time sensitive ID files.  This makes your data incredibly secure... WAAAAAAAY more secure than any microsoft product... but it is a pain in the but to make sure that you have the right id file talking to the right server.

I agree that installing into a different flder than the previous may have messed things up a little.
SOmetimes the upgrade does not recognize the previous installaton ad that can cause issues.

Glad you got it working !

I am using the same ID as I was using in previous installation in R7 folder. So id should not be an issue. I am not sure what do you mean by what type of installation. I installed the standard one with all the three clients (Notes, Designer and Administrator).
Notes installation creates a new Notes.ini file automatically in installation folder automatically. So not sure if notes.ini was pointing to wrong folder. Could it be a resigtry issue ?