For some files in your system that are not digitally signed, an error message ASN1 bad tag value met would appear when you install any new software or any critical updates for Win XP.
To fix this error, you can follow the steps given below, after which you will be able to download correct critical updates for WinXP, etc and your problem will be solved!
1. Basic step: Click START->RUN
2. Type SIGVERIF
3.Click ADVANCED -> then inside the SEARCH tab
4.Click on Look for other files
5.Then Down check the check box (Include Subfolders). Click on browse button. Then under the Windows Folder -> Select SYSTEM32 ->CatRoot. Then click OK button. Then click again OK in the SEARCH tab. Then click START on File Signature Verification.
6.After scanning you will get a list of files that have not been digitally signed. Now without closing this window, create a Folder name TEMP into your desktop.
NEXT FOLLOW THESE STEPS:
1. Go to start-> run and type C:\WINDOWS\SYSTEM32\CATROOT
2. Now search the list of files that are not digitally signed by comparing the files that you got in the previous step 6
3. Now select those files from C:\WINDOWS\SYSTEM32\CATROOT and cut and paste into the TEMP folder created into your desktop
4. THUS “ASN1 bad tag value met “error is fixed
5. Now delete the TEMP folder from desktop.
Thus now you again try to install any new software or any critical updates for XP, you can see the error being eliminated !!