Sudden, or seemingly sporadic, difficulty sending cdo emails

My site is having trouble sending group emails all of a sudden.  Below is an error message that I get.  Note that there is no error description.  Line 306 is the .Send line.  Anything you can tell me would be much appreciated!


Domain: domain-name
Organization: organization-name
Site User: User-Name
Role: Coach
Email: email-address[at]domain-name.com
When Occur: 8/22/2012 1:52:58 PM
Web Page: //www.webpage.com/communications/grp_email/send_email.asp
Line: 306
Column: -1
Source:  
Description:  
Err #:  
Com Err #: -2147220977
Category:  
URL: /communications/grp_email/send_email.asp
ASP Descr:  
REQUEST_METHOD: POST
SERVER_PORT: 80
HTTPS: off
LOCAL_ADDR: 216.xxx.xxx.1
REMOTE_ADDR: 66.xx.xxx.114
HTTP_USER_AGENT: Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0) Query STring:  
Form: asst_exists_863=y&asst_863=on&all_staff=on&staff_exists_716=y&staff_exists_580=y&staff_exists_717=y&all_contacts=on&contact_exists_1775=y&contact_exists_2539=y&contact_exists_2530=y&contact_exists_2545=y&contact_exists_2470=y&contact_exists_1920=y&contact_exists_1792=y&contact_exists_2535=y&contact_exists_2538=y&contact_exists_1408=y&contact_exists_1795=y&contact_exists_1935=y&contact_exists_2540=y&contact_exists_2468=y&contact_exists_1798=y&contact_exists_1797=y&contact_exists_2469=y&contact_exists_1799=y&contact_exists_1796=y&contact_exists_2541=y&contact_exists_1416=y&contact_exists_2536=y&contact_exists_2544=y&contact_exists_1419=y&contact_exists_1409=y&contact_exists_1818=y&contact_exists_1648=y&contact_exists_1926=y&contact_exists_2537=y&contact_exists_1410=y&all_parts=on&part_exists_32406=y&part_exists_36794=y&part_exists_32951=y&part_exists_32417=y&part_exists_36935=y&part_exists_36795=y&part_exists_32615=y&part_exists_36793=y&part_exists_25329=y&part_exists_253
 37=y&part_exists_36796=y&part_exists_25330=y&part_exists_32414=y&part_exists_37043=y&part_exists_32407=y&part_exists_32413=y&part_exists_36797=y&part_exists_36792=y&part_exists_36229=y&part_exists_36799=y&part_exists_36798=y&part_exists_30721=y&part_exists_25335=y&part_exists_36183=y&part_exists_37044=y&part_exists_36791=y&part_exists_36902=y&part_exists_32614=y&part_exists_36169=y&part_exists_28745=y&part_exists_36181=y&part_exists_28990=y&part_exists_25324=y&subject=Meet+this+Saturday&send_how=cc&message=Hi+cross+country+families%2C%0D%0A%0D%0AThis+Saturday+we+will+be+competing+at+Our+Lady+of+Mercy+in+Fayetteville%2C+GA.++The+address+is%3A+%0D%0A861+Georgia+279++%0D%0AFayetteville%2C+GA+30214%0D%0A%0D%0AWe+will+meet+at+the+school+at+7%3A00+AM.++The+first+race+begins+at+8%3A00+AM.++We+will+walk+the+course%2C+warm+up%2C+and+distribute+bib+numbers+prior+to+the+first+race.++Please+make+every+effort+to+be+there+on+time.++%0D%0A%0D%0AIf+any+parents+are+willing+to+bring+Gatorade+a
 nd+water+bottles%2C+please+let+me+know.++Last+year+we+made+a+great+effort+to+have+this+taken+care+of+at+every+meet.+Thank+you+in+advance+for+supporting+our+team%21%0D%0A%0D%0AIf+you+have+any+questions+or+concerns%2C+please+email+me.++We+have+had+a+great+start+to+our+season%21%0D%0A%0D%0AThanks%2C%0D%0ACoach+Mink&submit=Send+Email

**Question body edited to excluded company specific information**-JARmod101