[SOLVED] clean install revo 2.2 pl blank manager

hi,

I have a new modx revolution install
started working on it,
added tinyMCE and wayfinder
created some resources, snippets and a template
all works fine.

But now, a day later, I try to go to the manager again and it gives me a blank page.
when I try in a diffrent browser it gives me the login screen,
I log in and then again a blank page.

could this be a session problem or something?
maybe my previous session is still pending?

the front-end of the site still works fine btw

hope someont can help?
ps I allready posted this in a wrong forum:
https://forums.modx.com/thread/74578/manager-gives-blank-screen-after-login#dis-post-414124

If i remove all files and folders in core/cache/ the manager works again.
But only for one time, next time i log into the manager it gives a blank screen again. [ed. note: djemmers last edited this post 14 years, 6 months ago.]

could this be the problem:
http://tracker.modx.com/issues/5136
I am thinking it could be becaues when I delete the contents of the cache folder it works again.

but how to permanently fix...

my error log in cache
[2012-03-01 09:54:18] (ERROR @ /home/content/48/8154648/html/modx/core/model/modx/moduser.class.php : 310) PHP warning: session_regenerate_id() [<a href='function.session-regenerate-id'>function.session-regenerate-id</a>]: Cannot regenerate session id - headers already sent
[2012-03-01 09:54:18] (ERROR @ /home/content/48/8154648/html/modx/core/model/modx/modresponse.class.php : 264) PHP warning: Cannot modify header information - headers already sent by (output started at /home/content/48/8154648/html/modx/manager/index.php:75)

but I don't understand it

aha found it!

seems in my search to fix it I forgot to delete the echo lines I added to index.php in manager
after deleting them and clearing the core/cache folder one more time the manager worked perfectly from then on!