ckfinder / fckeditor will not upload files

I have ckfinder integrated with FCKEditor and there are files which just won't upload.

It seems to be a size problem, but I can't figure out what I've done wrong in the config.

I tested zip, gif, text and ppt files < 100K and they work fine. Over 100K will not upload. None of my pdf's will upload (even < 100K)

Here is my config file:

config.resourceType[1] = structNew();
config.resourceType[1].name = 'Files';
config.resourceType[1].url = config.baseUrl & 'files';
config.resourceType[1].directory = config.baseDir & 'files';
config.resourceType[1].maxSize = "10M";
config.resourceType[1].allowedExtensions = '7z,aiff,asf,avi,bmp,csv,doc,fla,flv,gif,gz,gzip,jpeg,jpg,mid,mov,mp3,mp4,mpc,mpeg,mpg,ods,odt,pdf,png,ppt,pxd,qt,ram,rar,rm,rmi,rmvb,rtf,sdc,sitd,swf,sxc,sxw,tar,tgz,tif,tiff,txt,vsd,wav,wma,wmv,xls,zip';
config.resourceType[1].deniedExtensions = '';

config.resourceType[2] = structNew();
config.resourceType[2].name = 'Images';
config.resourceType[2].url = config.baseUrl & 'images';
config.resourceType[2].directory = config.baseDir & 'images';
config.resourceType[2].maxSize = 0;
config.resourceType[2].allowedExtensions = 'bmp,gif,jpeg,jpg,png';
config.resourceType[2].deniedExtensions = '';

config.resourceType[3] = structNew();
config.resourceType[3].name = 'Flash';
config.resourceType[3].url = config.baseUrl & 'flash';
config.resourceType[3].directory = config.baseDir & 'flash';
config.resourceType[3].maxSize = 0;
config.resourceType[3].allowedExtensions = 'swf,flv';
config.resourceType[3].deniedExtensions = '';

can anyone help please?