Thats the Crystal export dll reporting that error back to CRD. Its caused by a memory leak in the dll. Make sure you are using Crystal Developer or Advanced and that you have installed the latest service pack and monthly hotfixes so you get the latest dlls where this problem has been fixed.
Actually, not strange at all. Here's why. Crystal have created special runtime dlls which are used by third party applications like CRD to read and export reports. Crystal itself does not use these dlls. So something can work quite happily in Crystal but not work from another application - and this is what is happening with you.
