Crystal Reports : Retrieving the COM class factory for component with CLSID {GUID} failed due to the following error: 80070005

If your crystal report is working locally and not on server it is permission problem. If you are using plesk then plesk user IWAM_plesk(default) and IUSR_siteusername must have persmissions on a lot of things, so just give them permission to whole [C:\] drive and you are got to go. Have fun..

After your reports start working try removing permissions for security. 

Solutions:

1. If possible change pool account to LocalSystem
2. Compile x86 version of your web app or web site
3. "Enable 32-bit Applications" should be true in your pool advanced settings