If an error occurs in mojoPortal, you generally will only see a page that tells you an error has occurred. This is because we have it configured to only show a friendly error message and not error details. Its bad idea to share any error information with the public as hackers may use this information for further attacks. In order to troubleshoot the error you first need to know what the error is.
Checking the mojoPrtal Log
mojoPortal logs all unhandled errors as well as some handled errors and info in our system log. You can view the log from Administration Menu > System Log. The log itself is just a text file located at /Data/currentlog.config, so you can also download it and read it locally using a text editor.
The newest errors will be at the bottom of the file. On a new installation, its normal to log a lot of errors at first because the database is empty until the setup page has run.
If there is nothing in the log or the file does not exist then its usually an indication of a site where the file system permissions are not configured correctly. The web process must have read permission on the whole web root folder tree and it must have read/write on the /Data folder and all files/folders beneath it.
Disable the Friendly Error Page and Show The Real Error
It is also possible to disable the friendly error page and have it show the error detail in the page. You can do this by editing in the Web.config file in the root of the web. Look for this: <customErrors mode="RemoteOnly"... and change it to this <customErrors mode="Off"...
After resolving the problems its best to change that back to RemoteOnly so that error details are not revealed to the public.
Once you can see the error, it may give you enough information to solve it. If you are not able to solve it yourself you can post in the forums and include the error detail. Please don't post large chuncks of your error log in the forums though, try to find just the relevant errors and if they are duplicated over and over just post one copy.