I just fresh install the DNN v4.4.1 and DB on SQL 2000 without any problems and bring up default DNN page.

But I got login failed when I login to site with admin or host account using by dnnadmin / dnnhost default password dispaying on default page.

Please someone help me to login.

Since you are able to login with the new user account, I would try using my instructions on how to reset a password via the database.  You can find these here http://mitchelsellers.com/Blogs/tabid/54/EntryID/23/Default.aspx

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-Mitchel Sellers
Microsoft MVP, ASPInsider, DNN MVP
CEO/Director of Development - IowaComputerGurus Inc.


Visit mitchelsellers.com for my mostly DNN Blog and support forum.

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I had this same problem recently with DNN 4x.  It seems that I may have logged in successfully one time as host.  After that, I could not log as host or admin. I deleted everything and re-installed. After that, all was OK.

I believe that my problem was the fact that I had the web.config file still open in Notepad after I had updated the connection string settings.  I believe that the Machine Keys settings in the web.config file were changed by DotNetNuke just after I logged in the first time.

Then,  for some reason, I believe that I clicked the Save button in Notepad again and after that, could not log in as host or admin.  I believe this action caused the new Machine Keys settings (under system.web) to be overwritten back to the original values as they were in the original release.config file.  I understand that you have to be very careful about preserving the values of your Machine Keys settings (by keeping a backup copy of them) if you are installing a subsequent update to DotNetNuke.