Dear Manju;
Thank you for reaching the Small Business Support Community.
If the Diag status light continues to flash upon restarting, the firmware image is damaged. Use the
TFTP utility to upgrade the firmware if you can not access the device through the GUI application. You can download the TFTP utility from the below link;
http://software.cisco.com/download/release.html?mdfid=282414010&flowid=784&softwareid=282465800&release=4.0.0.7&relind=AVAILABLE&rellifecycle=&reltype=latest
If the router is still operational and GUI accessible, you may just try to upgrade the firmware release version to the latest available v4.2.2.08;
http://software.cisco.com/download/release.html?mdfid=282414010&flowid=784&softwareid=282465789&release=4.2.2.08&relind=AVAILABLE&rellifecycle=&reltype=latest
Considering this is a an old RV042 I would also suggest you to restore to factory conditions, then reconfigure it manually, please check on chapter 5 on the admin guide for that matter;
http://www.cisco.com/en/US/docs/routers/csbr/rv0xx/administration/guide/rv0xx_AG_78-19576.pdf
If the problem persists you may try to get support from the available support channels in your country;
https://supportforums.cisco.com/community/netpro/small-business/sbcountrysupport
Please do not hesitate to reach me back if there is any further assistance I may help you with.
Kind regards,
Jeffrey Rodriguez S. .:|:.:|:.
Cisco Customer Support Engineer
*Please rate the Post so other will know when an answer has been found.
Jeffrey Rodriguez S. .:|:.:|:.
Cisco Customer Support Engineer
*Please rate the Post so other will know when an answer has been found.