Manager down in old installation

I have a several year old modx site, and the manager screen is now giving the error:

Deprecated: Assigning the return value of new by reference is deprecated in ....browsercheck.inc.php on line 16

I presume I need to update to the latest version, but how do I even find out which version is installed? (I do have ftp access)

You can eliminate the error by going to that file, and on that line number look for the & before the new statement. Just delete the &.

You can see the version in the upper right corner of the Manger page, or you can take a look at the manager/includes/version.inc.php file.

Thank you!

I'm now in, but getting these messages:

Warning: strftime() [function.strftime]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'UTC' for 'UTC/0.0/no DST' instead in ....mutate_settings.dynamic.php on line 480
Select the number of hours time difference between where you are and where the server is. Current time on server is [19:50:50], current time on server using the currently saved offset is [12:50:50].

Warning: strftime() [function.strftime]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'UTC' for 'UTC/0.0/no DST' instead in ...welcome.static.php on line 100

Is this something I need to worry about? I've set the correct offset in the config.

Yes, a mismatched timezone setting can cause problems accessing the database. Again, this is a PHP version issue.

There are a couple of ways you can set the timezone. I would suggest contacting your hosting company's tech support for the best way for their servers.